diff --git a/ext/intl/calendar/calendar.stub.php b/ext/intl/calendar/calendar.stub.php
index 078ecb0c2da..56602da0ec2 100644
--- a/ext/intl/calendar/calendar.stub.php
+++ b/ext/intl/calendar/calendar.stub.php
@@ -90,11 +90,10 @@ class IntlCalendar
     private function __construct() {}
 
     /**
-     * @param IntlTimeZone|DateTimeZone|string|null $timezone
      * @tentative-return-type
      * @alias intlcal_create_instance
      */
-    public static function createInstance($timezone = null, ?string $locale = null): ?IntlCalendar {}
+    public static function createInstance(IntlTimeZone|DateTimeZone|string|null $timezone = null, ?string $locale = null): ?IntlCalendar {}
 
     /**
      * @tentative-return-type
@@ -355,11 +354,9 @@ class IntlCalendar
     public function setTime(float $timestamp): bool {}
 
     /**
-     * @param IntlTimeZone|DateTimeZone|string|null $timezone
      * @tentative-return-type
-     * @alias intlcal_set_time_zone
      */
-    public function setTimeZone($timezone): bool {}
+    public function setTimeZone(IntlTimeZone|DateTimeZone|string|null $timezone): bool {}
 
     /**
      * @tentative-return-type
diff --git a/ext/intl/calendar/calendar_arginfo.h b/ext/intl/calendar/calendar_arginfo.h
index 9e050539b2e..415113b613a 100644
--- a/ext/intl/calendar/calendar_arginfo.h
+++ b/ext/intl/calendar/calendar_arginfo.h
@@ -1,11 +1,11 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: c014b88c9b6aa145ea20cc1f3fd719fe9f3d6966 */
+ * Stub hash: 2fc12d1fde65efbec4305f4934a3f4b25282a552 */
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_class_IntlCalendar___construct, 0, 0, 0)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_OBJ_INFO_EX(arginfo_class_IntlCalendar_createInstance, 0, 0, IntlCalendar, 1)
-	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, timezone, "null")
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, "null")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, locale, IS_STRING, 1, "null")
 ZEND_END_ARG_INFO()
 
@@ -165,7 +165,7 @@ ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_TYPE_INFO_EX(arginfo_class_IntlCalendar_set
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_TYPE_INFO_EX(arginfo_class_IntlCalendar_setTimeZone, 0, 1, _IS_BOOL, 0)
-	ZEND_ARG_INFO(0, timezone)
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, NULL)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_OBJ_TYPE_MASK_EX(arginfo_class_IntlCalendar_toDateTime, 0, 0, DateTime, MAY_BE_FALSE)
@@ -249,7 +249,7 @@ ZEND_FUNCTION(intlcal_set_lenient);
 ZEND_FUNCTION(intlcal_set_repeated_wall_time_option);
 ZEND_FUNCTION(intlcal_set_skipped_wall_time_option);
 ZEND_FUNCTION(intlcal_set_time);
-ZEND_FUNCTION(intlcal_set_time_zone);
+ZEND_METHOD(IntlCalendar, setTimeZone);
 ZEND_FUNCTION(intlcal_to_date_time);
 ZEND_METHOD(IntlGregorianCalendar, createFromDate);
 ZEND_METHOD(IntlGregorianCalendar, createFromDateTime);
@@ -305,7 +305,7 @@ static const zend_function_entry class_IntlCalendar_methods[] = {
 	ZEND_RAW_FENTRY("setRepeatedWallTimeOption", zif_intlcal_set_repeated_wall_time_option, arginfo_class_IntlCalendar_setRepeatedWallTimeOption, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("setSkippedWallTimeOption", zif_intlcal_set_skipped_wall_time_option, arginfo_class_IntlCalendar_setSkippedWallTimeOption, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("setTime", zif_intlcal_set_time, arginfo_class_IntlCalendar_setTime, ZEND_ACC_PUBLIC, NULL, NULL)
-	ZEND_RAW_FENTRY("setTimeZone", zif_intlcal_set_time_zone, arginfo_class_IntlCalendar_setTimeZone, ZEND_ACC_PUBLIC, NULL, NULL)
+	ZEND_ME(IntlCalendar, setTimeZone, arginfo_class_IntlCalendar_setTimeZone, ZEND_ACC_PUBLIC)
 	ZEND_RAW_FENTRY("toDateTime", zif_intlcal_to_date_time, arginfo_class_IntlCalendar_toDateTime, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_FE_END
 };
diff --git a/ext/intl/calendar/calendar_methods.cpp b/ext/intl/calendar/calendar_methods.cpp
index d668cd66df9..c404286fe09 100644
--- a/ext/intl/calendar/calendar_methods.cpp
+++ b/ext/intl/calendar/calendar_methods.cpp
@@ -72,21 +72,21 @@ U_CFUNC PHP_METHOD(IntlCalendar, __construct)
 
 U_CFUNC PHP_FUNCTION(intlcal_create_instance)
 {
-	zval		*zv_timezone	= NULL;
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
 	char	        *locale_str	= NULL;
 	size_t		locale_len      = 0;
-	TimeZone	*timeZone;
 	UErrorCode	status			= U_ZERO_ERROR;
 	intl_error_reset(NULL);
 
 	ZEND_PARSE_PARAMETERS_START(0, 2)
 		Z_PARAM_OPTIONAL
-		Z_PARAM_ZVAL(zv_timezone)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
 		Z_PARAM_STRING_OR_NULL(locale_str, locale_len)
 	ZEND_PARSE_PARAMETERS_END();
 
-	timeZone = timezone_process_timezone_argument(zv_timezone, NULL);
-	if (timeZone == NULL) {
+	TimeZone *timeZone = timezone_process_timezone_argument(timezone_object, timezone_string, nullptr);
+	if (timeZone == nullptr) {
 		RETURN_NULL();
 	}
 
@@ -296,26 +296,28 @@ U_CFUNC PHP_FUNCTION(intlcal_add)
 	RETURN_TRUE;
 }
 
+/* {{{ Set formatter's timezone. */
 U_CFUNC PHP_FUNCTION(intlcal_set_time_zone)
 {
-	zval			*zv_timezone;
-	TimeZone		*timeZone;
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
+
 	CALENDAR_METHOD_INIT_VARS;
 
-	if (zend_parse_method_parameters(ZEND_NUM_ARGS(), getThis(),
-			"Oz!", &object, Calendar_ce_ptr, &zv_timezone) == FAILURE) {
-		RETURN_THROWS();
-	}
+	ZEND_PARSE_PARAMETERS_START(2, 2)
+		Z_PARAM_OBJECT_OF_CLASS(object, Calendar_ce_ptr)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
+	ZEND_PARSE_PARAMETERS_END();
 
 	CALENDAR_METHOD_FETCH_OBJECT;
 
-	if (zv_timezone == NULL) {
+	if (timezone_object == nullptr && timezone_string == nullptr) {
 		RETURN_TRUE; /* the method does nothing if passed null */
 	}
 
-	timeZone = timezone_process_timezone_argument(zv_timezone,
-			CALENDAR_ERROR_P(co));
-	if (timeZone == NULL) {
+	TimeZone *timeZone = timezone_process_timezone_argument(
+		timezone_object, timezone_string, CALENDAR_ERROR_P(co));
+	if (timeZone == nullptr) {
 		RETURN_FALSE;
 	}
 
@@ -324,6 +326,34 @@ U_CFUNC PHP_FUNCTION(intlcal_set_time_zone)
 	RETURN_TRUE;
 }
 
+U_CFUNC PHP_METHOD(IntlCalendar, setTimeZone)
+{
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
+
+	CALENDAR_METHOD_INIT_VARS;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
+	ZEND_PARSE_PARAMETERS_END();
+
+	object = ZEND_THIS;
+	CALENDAR_METHOD_FETCH_OBJECT;
+
+	if (timezone_object == nullptr && timezone_string == nullptr) {
+		RETURN_TRUE; /* the method does nothing if passed null */
+	}
+
+	TimeZone *timeZone = timezone_process_timezone_argument(
+		timezone_object, timezone_string, CALENDAR_ERROR_P(co));
+	if (timeZone == nullptr) {
+		RETURN_FALSE;
+	}
+
+	co->ucal->adoptTimeZone(timeZone);
+
+	RETURN_TRUE;
+}
 
 static void _php_intlcal_before_after(
 		UBool (Calendar::*func)(const Calendar&, UErrorCode&) const,
diff --git a/ext/intl/calendar/gregoriancalendar_methods.cpp b/ext/intl/calendar/gregoriancalendar_methods.cpp
index 8796e01f638..0cc3a94d4c5 100644
--- a/ext/intl/calendar/gregoriancalendar_methods.cpp
+++ b/ext/intl/calendar/gregoriancalendar_methods.cpp
@@ -77,7 +77,8 @@ static bool set_gregorian_calendar_time_zone(GregorianCalendar *gcal, UErrorCode
 
 static void _php_intlgregcal_constructor_body(INTERNAL_FUNCTION_PARAMETERS, bool is_constructor)
 {
-	zval		*tz_object	= NULL;
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
 	zval		args_a[6],
 				*args		= &args_a[0];
 	char		*locale		= NULL;
@@ -112,15 +113,23 @@ static void _php_intlgregcal_constructor_body(INTERNAL_FUNCTION_PARAMETERS, bool
 
 	// argument parsing
 	if (variant <= 2) {
-		if (zend_parse_parameters(MIN(ZEND_NUM_ARGS(), 2),
-                               "|z!s!", &tz_object, &locale, &locale_len) == FAILURE) {
-                       RETURN_THROWS();
-               }
-       }
-       if (variant > 2 && zend_parse_parameters(ZEND_NUM_ARGS(),
-                       "lll|lll", &largs[0], &largs[1], &largs[2], &largs[3], &largs[4],
-                       &largs[5]) == FAILURE) {
-               RETURN_THROWS();
+		/* These dummy variables are needed because the 2 param constructor allows trailing nulls... */
+		zval *dummy1, *dummy2, *dummy3, *dummy4;
+		ZEND_PARSE_PARAMETERS_START(0, 6)
+			Z_PARAM_OPTIONAL
+			Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
+			Z_PARAM_STRING_OR_NULL(locale, locale_len)
+			Z_PARAM_ZVAL(dummy1)
+			Z_PARAM_ZVAL(dummy2)
+			Z_PARAM_ZVAL(dummy3)
+			Z_PARAM_ZVAL(dummy4)
+		ZEND_PARSE_PARAMETERS_END();
+	}
+	if (variant > 2
+		&& zend_parse_parameters(ZEND_NUM_ARGS(), "lll|lll",
+			&largs[0], &largs[1], &largs[2], &largs[3], &largs[4], &largs[5]) == FAILURE
+	) {
+		RETURN_THROWS();
 	}
 
 	// instantion of ICU object
@@ -134,8 +143,8 @@ static void _php_intlgregcal_constructor_body(INTERNAL_FUNCTION_PARAMETERS, bool
 
 	if (variant <= 2) {
 		// From timezone and locale (0 to 2 arguments)
-		TimeZone *tz = timezone_process_timezone_argument(tz_object, NULL);
-		if (tz == NULL) {
+		TimeZone *tz = timezone_process_timezone_argument(timezone_object, timezone_string, nullptr);
+		if (tz == nullptr) {
 			// TODO: Exception should always occur already?
 			if (!EG(exception)) {
 				zend_throw_exception(IntlException_ce_ptr, "Constructor failed", 0);
diff --git a/ext/intl/dateformat/dateformat.stub.php b/ext/intl/dateformat/dateformat.stub.php
index 7582af2717f..89ebc5f61c0 100644
--- a/ext/intl/dateformat/dateformat.stub.php
+++ b/ext/intl/dateformat/dateformat.stub.php
@@ -32,20 +32,18 @@ class IntlDateFormatter
     public const int TRADITIONAL = UNKNOWN;
 
     /**
-     * @param IntlTimeZone|DateTimeZone|string|null $timezone
      * @param IntlCalendar|int|null $calendar
      */
     public function __construct(
         ?string $locale,
         int $dateType = IntlDateFormatter::FULL,
         int $timeType = IntlDateFormatter::FULL,
-        $timezone = null,
+        IntlTimeZone|DateTimeZone|string|null $timezone = null,
         $calendar = null,
         ?string $pattern = null
     ) {}
 
     /**
-     * @param IntlTimeZone|DateTimeZone|string|null $timezone
      * @tentative-return-type
      * @alias datefmt_create
      */
@@ -53,7 +51,7 @@ class IntlDateFormatter
         ?string $locale,
         int $dateType = IntlDateFormatter::FULL,
         int $timeType = IntlDateFormatter::FULL,
-        $timezone = null,
+        IntlTimeZone|DateTimeZone|string|null $timezone = null,
         IntlCalendar|int|null $calendar = null,
         ?string $pattern = null
     ): ?IntlDateFormatter {}
@@ -101,11 +99,9 @@ class IntlDateFormatter
     public function getTimeZone(): IntlTimeZone|false {}
 
     /**
-     * @param IntlTimeZone|DateTimeZone|string|null $timezone
      * @tentative-return-type
-     * @alias datefmt_set_timezone
      */
-    public function setTimeZone($timezone): bool {}
+    public function setTimeZone(IntlTimeZone|DateTimeZone|string|null $timezone): bool {}
 
     /**
      * @tentative-return-type
diff --git a/ext/intl/dateformat/dateformat_arginfo.h b/ext/intl/dateformat/dateformat_arginfo.h
index b57cb79468f..d6d0306506f 100644
--- a/ext/intl/dateformat/dateformat_arginfo.h
+++ b/ext/intl/dateformat/dateformat_arginfo.h
@@ -1,11 +1,11 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 56b66b1b51220ddbff698ec4c9a6ae60f3e0bfb0 */
+ * Stub hash: 160d05ec65c45b66b13eaecbef20b3c59bfb33d1 */
 
 ZEND_BEGIN_ARG_INFO_EX(arginfo_class_IntlDateFormatter___construct, 0, 0, 1)
 	ZEND_ARG_TYPE_INFO(0, locale, IS_STRING, 1)
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, dateType, IS_LONG, 0, "IntlDateFormatter::FULL")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, timeType, IS_LONG, 0, "IntlDateFormatter::FULL")
-	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, timezone, "null")
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, "null")
 	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, calendar, "null")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, pattern, IS_STRING, 1, "null")
 ZEND_END_ARG_INFO()
@@ -14,7 +14,7 @@ ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_OBJ_INFO_EX(arginfo_class_IntlDateFormatter
 	ZEND_ARG_TYPE_INFO(0, locale, IS_STRING, 1)
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, dateType, IS_LONG, 0, "IntlDateFormatter::FULL")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, timeType, IS_LONG, 0, "IntlDateFormatter::FULL")
-	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, timezone, "null")
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, "null")
 	ZEND_ARG_OBJ_TYPE_MASK(0, calendar, IntlCalendar, MAY_BE_LONG|MAY_BE_NULL, "null")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, pattern, IS_STRING, 1, "null")
 ZEND_END_ARG_INFO()
@@ -40,7 +40,7 @@ ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_OBJ_TYPE_MASK_EX(arginfo_class_IntlDateForm
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_TYPE_INFO_EX(arginfo_class_IntlDateFormatter_setTimeZone, 0, 1, _IS_BOOL, 0)
-	ZEND_ARG_INFO(0, timezone)
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, NULL)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_TENTATIVE_RETURN_TYPE_INFO_EX(arginfo_class_IntlDateFormatter_setPattern, 0, 1, _IS_BOOL, 0)
@@ -100,7 +100,7 @@ ZEND_FUNCTION(datefmt_set_calendar);
 ZEND_FUNCTION(datefmt_get_timezone_id);
 ZEND_FUNCTION(datefmt_get_calendar_object);
 ZEND_FUNCTION(datefmt_get_timezone);
-ZEND_FUNCTION(datefmt_set_timezone);
+ZEND_METHOD(IntlDateFormatter, setTimeZone);
 ZEND_FUNCTION(datefmt_set_pattern);
 ZEND_FUNCTION(datefmt_get_pattern);
 ZEND_FUNCTION(datefmt_get_locale);
@@ -124,7 +124,7 @@ static const zend_function_entry class_IntlDateFormatter_methods[] = {
 	ZEND_RAW_FENTRY("getTimeZoneId", zif_datefmt_get_timezone_id, arginfo_class_IntlDateFormatter_getTimeZoneId, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("getCalendarObject", zif_datefmt_get_calendar_object, arginfo_class_IntlDateFormatter_getCalendarObject, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("getTimeZone", zif_datefmt_get_timezone, arginfo_class_IntlDateFormatter_getTimeZone, ZEND_ACC_PUBLIC, NULL, NULL)
-	ZEND_RAW_FENTRY("setTimeZone", zif_datefmt_set_timezone, arginfo_class_IntlDateFormatter_setTimeZone, ZEND_ACC_PUBLIC, NULL, NULL)
+	ZEND_ME(IntlDateFormatter, setTimeZone, arginfo_class_IntlDateFormatter_setTimeZone, ZEND_ACC_PUBLIC)
 	ZEND_RAW_FENTRY("setPattern", zif_datefmt_set_pattern, arginfo_class_IntlDateFormatter_setPattern, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("getPattern", zif_datefmt_get_pattern, arginfo_class_IntlDateFormatter_getPattern, ZEND_ACC_PUBLIC, NULL, NULL)
 	ZEND_RAW_FENTRY("getLocale", zif_datefmt_get_locale, arginfo_class_IntlDateFormatter_getLocale, ZEND_ACC_PUBLIC, NULL, NULL)
diff --git a/ext/intl/dateformat/dateformat_attrcpp.cpp b/ext/intl/dateformat/dateformat_attrcpp.cpp
index f95cc0f8de5..13dadc9c969 100644
--- a/ext/intl/dateformat/dateformat_attrcpp.cpp
+++ b/ext/intl/dateformat/dateformat_attrcpp.cpp
@@ -81,21 +81,46 @@ U_CFUNC PHP_FUNCTION(datefmt_get_timezone)
 /* {{{ Set formatter's timezone. */
 U_CFUNC PHP_FUNCTION(datefmt_set_timezone)
 {
-	zval		*timezone_zv;
-	TimeZone	*timezone;
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
 
 	DATE_FORMAT_METHOD_INIT_VARS;
 
-	if ( zend_parse_method_parameters(ZEND_NUM_ARGS(), getThis(),
-			"Oz", &object, IntlDateFormatter_ce_ptr, &timezone_zv) == FAILURE) {
-		RETURN_THROWS();
-	}
+	ZEND_PARSE_PARAMETERS_START(2, 2)
+		Z_PARAM_OBJECT_OF_CLASS(object, IntlDateFormatter_ce_ptr)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
+	ZEND_PARSE_PARAMETERS_END();
 
 	DATE_FORMAT_METHOD_FETCH_OBJECT;
 
-	timezone = timezone_process_timezone_argument(timezone_zv,
-			INTL_DATA_ERROR_P(dfo));
-	if (timezone == NULL) {
+	TimeZone *timezone = timezone_process_timezone_argument(
+		timezone_object, timezone_string, INTL_DATA_ERROR_P(dfo));
+	if (timezone == nullptr) {
+		RETURN_FALSE;
+	}
+
+	fetch_datefmt(dfo)->adoptTimeZone(timezone);
+
+	RETURN_TRUE;
+}
+
+U_CFUNC PHP_METHOD(IntlDateFormatter, setTimeZone)
+{
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
+
+	DATE_FORMAT_METHOD_INIT_VARS;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
+	ZEND_PARSE_PARAMETERS_END();
+
+	object = ZEND_THIS;
+	DATE_FORMAT_METHOD_FETCH_OBJECT;
+
+	TimeZone *timezone = timezone_process_timezone_argument(
+		timezone_object, timezone_string, INTL_DATA_ERROR_P(dfo));
+	if (timezone == nullptr) {
 		RETURN_FALSE;
 	}
 
diff --git a/ext/intl/dateformat/dateformat_create.cpp b/ext/intl/dateformat/dateformat_create.cpp
index 2be1d816374..d2d65bc2673 100644
--- a/ext/intl/dateformat/dateformat_create.cpp
+++ b/ext/intl/dateformat/dateformat_create.cpp
@@ -59,7 +59,8 @@ static zend_result datefmt_ctor(INTERNAL_FUNCTION_PARAMETERS)
 	Calendar *cal = NULL;
 	zend_long	calendar_type;
 	bool		calendar_owned;
-	zval		*timezone_zv	= NULL;
+	zend_object *timezone_object = nullptr;
+	zend_string *timezone_string = nullptr;
 	TimeZone	*timezone	= NULL;
 	bool		explicit_tz;
 	char*       pattern_str		= NULL;
@@ -76,7 +77,7 @@ static zend_result datefmt_ctor(INTERNAL_FUNCTION_PARAMETERS)
 		Z_PARAM_OPTIONAL
 		Z_PARAM_LONG(date_type)
 		Z_PARAM_LONG(time_type)
-		Z_PARAM_ZVAL(timezone_zv)
+		Z_PARAM_OBJ_OR_STR_OR_NULL(timezone_object, timezone_string)
 		Z_PARAM_OBJ_OF_CLASS_OR_LONG_OR_NULL(calendar_obj, Calendar_ce_ptr, calendar_long, calendar_is_null)
 		Z_PARAM_STRING_OR_NULL(pattern_str, pattern_str_len)
 	ZEND_PARSE_PARAMETERS_END_EX(return FAILURE);
@@ -120,13 +121,12 @@ static zend_result datefmt_ctor(INTERNAL_FUNCTION_PARAMETERS)
 	}
 
 	/* process timezone */
-	explicit_tz = timezone_zv != NULL && Z_TYPE_P(timezone_zv) != IS_NULL;
+	explicit_tz = timezone_object != nullptr || timezone_string != nullptr;
 
 	if (explicit_tz || calendar_owned ) {
 		//we have an explicit time zone or a non-object calendar
-		timezone = timezone_process_timezone_argument(timezone_zv,
-				INTL_DATA_ERROR_P(dfo));
-		if (timezone == NULL) {
+		timezone = timezone_process_timezone_argument(timezone_object, timezone_string, INTL_DATA_ERROR_P(dfo));
+		if (timezone == nullptr) {
 			goto error;
 		}
 	}
diff --git a/ext/intl/msgformat/msgformat_helpers.cpp b/ext/intl/msgformat/msgformat_helpers.cpp
index 080dba6cfe2..e734b2df27b 100644
--- a/ext/intl/msgformat/msgformat_helpers.cpp
+++ b/ext/intl/msgformat/msgformat_helpers.cpp
@@ -341,9 +341,7 @@ static void umsg_set_timezone(MessageFormatter_object *mfo,
 		}
 
 		if (used_tz == NULL) {
-			zval nullzv;
-			ZVAL_NULL(&nullzv);
-			used_tz = timezone_process_timezone_argument(&nullzv, &err);
+			used_tz = timezone_process_timezone_argument(nullptr, nullptr, &err);
 			if (used_tz == NULL) {
 				continue;
 			}
diff --git a/ext/intl/php_intl.stub.php b/ext/intl/php_intl.stub.php
index af1ce6f1edb..d2ca22c6d29 100644
--- a/ext/intl/php_intl.stub.php
+++ b/ext/intl/php_intl.stub.php
@@ -173,8 +173,7 @@ class IntlException extends Exception
 
 /* calendar */
 
-/** @param IntlTimeZone|DateTimeZone|string|null $timezone */
-function intlcal_create_instance($timezone = null, ?string $locale = null): ?IntlCalendar {}
+function intlcal_create_instance(IntlTimeZone|DateTimeZone|string|null $timezone = null, ?string $locale = null): ?IntlCalendar {}
 
 function intlcal_get_keyword_values_for_locale(string $keyword, string $locale, bool $onlyCommon): IntlIterator|false {}
 
@@ -194,8 +193,7 @@ function intlcal_set_time(IntlCalendar $calendar, float $timestamp): bool {}
 
 function intlcal_add(IntlCalendar $calendar, int $field, int $value): bool {}
 
-/** @param IntlTimeZone|DateTimeZone|string|null $timezone */
-function intlcal_set_time_zone(IntlCalendar $calendar, $timezone): bool {}
+function intlcal_set_time_zone(IntlCalendar $calendar, IntlTimeZone|DateTimeZone|string|null $timezone): bool {}
 
 function intlcal_after(IntlCalendar $calendar, IntlCalendar $other): bool {}
 
@@ -328,12 +326,11 @@ function intl_error_name(int $errorCode): string {}
 
 /* dateformat */
 
-/** @param IntlTimeZone|DateTimeZone|string|null $timezone */
 function datefmt_create(
     ?string $locale,
     int $dateType = IntlDateFormatter::FULL,
     int $timeType = IntlDateFormatter::FULL,
-    $timezone = null,
+    IntlTimeZone|DateTimeZone|string|null $timezone = null,
     IntlCalendar|int|null $calendar = null,
     ?string $pattern = null
 ): ?IntlDateFormatter {}
@@ -352,8 +349,7 @@ function datefmt_get_calendar_object(IntlDateFormatter $formatter): IntlCalendar
 
 function datefmt_get_timezone(IntlDateFormatter $formatter): IntlTimeZone|false {}
 
-/** @param IntlTimeZone|DateTimeZone|string|null $timezone */
-function datefmt_set_timezone(IntlDateFormatter $formatter, $timezone): bool {}
+function datefmt_set_timezone(IntlDateFormatter $formatter, IntlTimeZone|DateTimeZone|string|null $timezone): bool {}
 
 function datefmt_set_pattern(IntlDateFormatter $formatter, string $pattern): bool {}
 
diff --git a/ext/intl/php_intl_arginfo.h b/ext/intl/php_intl_arginfo.h
index 8f3ba504154..012e274296a 100644
--- a/ext/intl/php_intl_arginfo.h
+++ b/ext/intl/php_intl_arginfo.h
@@ -1,8 +1,8 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: bd78e0b6aec5c52b13f83e3c3cc7770c942d7c20 */
+ * Stub hash: 3fa507cf4ace635ae620050db9662b3979890bc1 */
 
 ZEND_BEGIN_ARG_WITH_RETURN_OBJ_INFO_EX(arginfo_intlcal_create_instance, 0, 0, IntlCalendar, 1)
-	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, timezone, "null")
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, "null")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, locale, IS_STRING, 1, "null")
 ZEND_END_ARG_INFO()
 
@@ -40,7 +40,7 @@ ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_intlcal_set_time_zone, 0, 2, _IS_BOOL, 0)
 	ZEND_ARG_OBJ_INFO(0, calendar, IntlCalendar, 0)
-	ZEND_ARG_INFO(0, timezone)
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, NULL)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_intlcal_after, 0, 2, _IS_BOOL, 0)
@@ -280,7 +280,7 @@ ZEND_BEGIN_ARG_WITH_RETURN_OBJ_INFO_EX(arginfo_datefmt_create, 0, 1, IntlDateFor
 	ZEND_ARG_TYPE_INFO(0, locale, IS_STRING, 1)
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, dateType, IS_LONG, 0, "IntlDateFormatter::FULL")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, timeType, IS_LONG, 0, "IntlDateFormatter::FULL")
-	ZEND_ARG_INFO_WITH_DEFAULT_VALUE(0, timezone, "null")
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, "null")
 	ZEND_ARG_OBJ_TYPE_MASK(0, calendar, IntlCalendar, MAY_BE_LONG|MAY_BE_NULL, "null")
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, pattern, IS_STRING, 1, "null")
 ZEND_END_ARG_INFO()
@@ -312,7 +312,7 @@ ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_datefmt_set_timezone, 0, 2, _IS_BOOL, 0)
 	ZEND_ARG_OBJ_INFO(0, formatter, IntlDateFormatter, 0)
-	ZEND_ARG_INFO(0, timezone)
+	ZEND_ARG_OBJ_TYPE_MASK(0, timezone, IntlTimeZone|DateTimeZone, MAY_BE_STRING|MAY_BE_NULL, NULL)
 ZEND_END_ARG_INFO()
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_datefmt_set_pattern, 0, 2, _IS_BOOL, 0)
diff --git a/ext/intl/tests/dateformat_setTimeZone_error.phpt b/ext/intl/tests/dateformat_setTimeZone_error.phpt
index 633d385323a..08ed8876d2f 100644
--- a/ext/intl/tests/dateformat_setTimeZone_error.phpt
+++ b/ext/intl/tests/dateformat_setTimeZone_error.phpt
@@ -12,17 +12,16 @@ $df = new IntlDateFormatter(NULL, 0, 0);
 
 try {
 	$df->setTimeZone(array());
-} catch (IntlException $e) {
-	echo $e->getMessage() . PHP_EOL;
+} catch (Throwable $e) {
+	echo $e::class, ': ', $e->getMessage(), PHP_EOL;
 }
 
 try {
 	$df->setTimeZone('non existing timezone');
-} catch (IntlException $e) {
-	echo $e->getMessage();
+} catch (Throwable $e) {
+	echo $e::class, ': ', $e->getMessage(), PHP_EOL;
 }
 ?>
---EXPECTF--
-Warning: Array to string conversion in %s on line %d
-IntlDateFormatter::setTimeZone(): No such time zone: "Array"
-IntlDateFormatter::setTimeZone(): No such time zone: "non existing timezone"
+--EXPECT--
+TypeError: IntlDateFormatter::setTimeZone(): Argument #1 ($timezone) must be of type object|string|null, array given
+IntlException: IntlDateFormatter::setTimeZone(): No such time zone: "non existing timezone"
diff --git a/ext/intl/timezone/timezone_class.cpp b/ext/intl/timezone/timezone_class.cpp
index 0737d994231..b5aed942d1c 100644
--- a/ext/intl/timezone/timezone_class.cpp
+++ b/ext/intl/timezone/timezone_class.cpp
@@ -131,73 +131,85 @@ static void timezone_throw_exception_with_call_location(const char *msg, const c
 }
 
 /* {{{ timezone_process_timezone_argument
- * TimeZone argument processor. outside_error may be NULL (for static functions/constructors) */
-U_CFUNC TimeZone *timezone_process_timezone_argument(zval *zv_timezone,
-													 intl_error *outside_error)
+ * TimeZone argument processor. outside_error may be nullptr (for static functions/constructors) */
+U_CFUNC TimeZone *timezone_process_timezone_argument(
+	zend_object *timezone_object, zend_string *timezone_string, intl_error *outside_error)
 {
-	zval		local_zv_tz;
 	std::unique_ptr<TimeZone>	timeZone;
+	bool free_string = false;
 
-	if (zv_timezone == NULL || Z_TYPE_P(zv_timezone) == IS_NULL) {
+	if (timezone_object == nullptr && timezone_string == nullptr) {
 		timelib_tzinfo *tzinfo = get_timezone_info();
-		ZVAL_STRING(&local_zv_tz, tzinfo->name);
-		zv_timezone = &local_zv_tz;
-	} else {
-		ZVAL_NULL(&local_zv_tz);
+		timezone_string = zend_string_init(tzinfo->name, strlen(tzinfo->name), false);
+		free_string = true;
 	}
 
-	if (Z_TYPE_P(zv_timezone) == IS_OBJECT &&
-			instanceof_function(Z_OBJCE_P(zv_timezone), TimeZone_ce_ptr)) {
-		TimeZone_object *to = Z_INTL_TIMEZONE_P(zv_timezone);
+	if (timezone_object != nullptr) {
+		if (instanceof_function(timezone_object->ce, TimeZone_ce_ptr)) {
+			const TimeZone_object *to = php_intl_timezone_fetch_object(timezone_object);
 
-		if (to->utimezone == NULL) {
-			timezone_throw_exception_with_call_location("passed IntlTimeZone is not "
-				"properly constructed", NULL);
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
-		}
-		timeZone = std::unique_ptr<TimeZone>(to->utimezone->clone());
-		if (UNEXPECTED(timeZone == NULL)) {
-			timezone_throw_exception_with_call_location("could not clone TimeZone", NULL);
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
-		}
-	} else if (Z_TYPE_P(zv_timezone) == IS_OBJECT &&
-			instanceof_function(Z_OBJCE_P(zv_timezone), php_date_get_timezone_ce())) {
+			if (UNEXPECTED(to->utimezone == nullptr)) {
+				timezone_throw_exception_with_call_location(
+					"passed IntlTimeZone is not properly constructed",nullptr);
+				return nullptr;
+			}
+			timeZone = std::unique_ptr<TimeZone>(to->utimezone->clone());
+			if (UNEXPECTED(timeZone == nullptr)) {
+				timezone_throw_exception_with_call_location("could not clone TimeZone", nullptr);
+				return nullptr;
+			}
+			// well, this is included by the centralized C intl part so the "smart" part can't go further
+			return timeZone.release();
+		} else if (instanceof_function(timezone_object->ce, php_date_get_timezone_ce())) {
+			php_timezone_obj *tz_obj = php_timezone_obj_from_obj(timezone_object);
 
-		php_timezone_obj *tzobj = Z_PHPTIMEZONE_P(zv_timezone);
-
-		zval_ptr_dtor_str(&local_zv_tz);
-		return timezone_convert_datetimezone(tzobj->type, tzobj, 0, outside_error);
-	} else {
-		UnicodeString	id;
-		UErrorCode		status = U_ZERO_ERROR; /* outside_error may be NULL */
-		if (!try_convert_to_string(zv_timezone)) {
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
-		}
-		if (intl_stringFromChar(id, Z_STRVAL_P(zv_timezone), Z_STRLEN_P(zv_timezone),
-				&status) == FAILURE) {
-			timezone_throw_exception_with_call_location("Time zone identifier given is not a "
-				"valid UTF-8 string", NULL);
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
-		}
-		timeZone = std::unique_ptr<TimeZone>(TimeZone::createTimeZone(id));
-		if (UNEXPECTED(timeZone == NULL)) {
-			timezone_throw_exception_with_call_location("Could not create time zone", NULL);
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
-		}
-		if (*timeZone == TimeZone::getUnknown()) {
-			timezone_throw_exception_with_call_location("No such time zone: ", Z_STRVAL_P(zv_timezone));
-			zval_ptr_dtor_str(&local_zv_tz);
-			return NULL;
+			return timezone_convert_datetimezone(tz_obj->type, tz_obj, false, outside_error);
+		} else {
+			zval tmp;
+			zend_result status = timezone_object->handlers->cast_object(timezone_object, &tmp, IS_STRING);
+			if (EXPECTED(status == SUCCESS)) {
+				timezone_string = Z_STR(tmp);
+				free_string = true;
+			} else {
+				if (!EG(exception)) {
+					// TODO Proper type error
+					zend_throw_error(nullptr, "Object of class %s could not be converted to string", ZSTR_VAL(timezone_object->ce->name));
+				}
+				return nullptr;
+			}
 		}
 	}
 
-	zval_ptr_dtor_str(&local_zv_tz);
+	ZEND_ASSERT(timezone_string != nullptr);
+	UnicodeString id;
+	UErrorCode status = U_ZERO_ERROR; /* outside_error may be nullptr */
 
+	if (UNEXPECTED(intl_stringFromChar(id, ZSTR_VAL(timezone_string), ZSTR_LEN(timezone_string), &status) == FAILURE)) {
+		timezone_throw_exception_with_call_location("Time zone identifier given is not a valid UTF-8 string", nullptr);
+		if (free_string) {
+			zend_string_release_ex(timezone_string, false);
+		}
+		return nullptr;
+	}
+
+	timeZone = std::unique_ptr<TimeZone>(TimeZone::createTimeZone(id));
+	if (UNEXPECTED(timeZone == nullptr)) {
+		timezone_throw_exception_with_call_location("Could not create time zone",nullptr);
+		if (free_string) {
+			zend_string_release_ex(timezone_string, false);
+		}
+		return nullptr;
+	}
+	if (UNEXPECTED(*timeZone == TimeZone::getUnknown())) {
+		timezone_throw_exception_with_call_location("No such time zone: ", ZSTR_VAL(timezone_string));
+		if (free_string) {
+			zend_string_release_ex(timezone_string, false);
+		}
+		return nullptr;
+	}
+	if (free_string) {
+		zend_string_release_ex(timezone_string, false);
+	}
 	// well, this is included by the centralized C intl part so the "smart" part can't go further
 	return timeZone.release();
 }
diff --git a/ext/intl/timezone/timezone_class.h b/ext/intl/timezone/timezone_class.h
index 08b78369e6f..bbfd8adcae2 100644
--- a/ext/intl/timezone/timezone_class.h
+++ b/ext/intl/timezone/timezone_class.h
@@ -67,7 +67,7 @@ static inline TimeZone_object *php_intl_timezone_fetch_object(zend_object *obj)
 	}
 
 zval *timezone_convert_to_datetimezone(const TimeZone *timeZone, intl_error *outside_error, zval *ret);
-TimeZone *timezone_process_timezone_argument(zval *zv_timezone, intl_error *error);
+TimeZone *timezone_process_timezone_argument(zend_object *timezone_object, zend_string *timezone_string, intl_error *error);
 
 void timezone_object_construct(const TimeZone *zone, zval *object, int owned);