diff --git a/ext/date/tests/bug36988.phpt b/ext/date/tests/bug36988.phpt
index e9fd69d7ef6..d35e58939aa 100644
--- a/ext/date/tests/bug36988.phpt
+++ b/ext/date/tests/bug36988.phpt
@@ -1,5 +1,7 @@
 --TEST--
 Bug #36988 (mktime freezes on long numbers)
+--INI--
+date.timezone=GMT
 --FILE--
 <?php
 $start = microtime(true);
diff --git a/ext/date/tests/bug37017.phpt b/ext/date/tests/bug37017.phpt
index ce438452b1e..61dc8ba383f 100644
--- a/ext/date/tests/bug37017.phpt
+++ b/ext/date/tests/bug37017.phpt
@@ -1,5 +1,7 @@
 --TEST--
 Bug #37017 (strtotime fails before 13:00:00 with some time zones identifiers).
+--INI--
+date.timezone=GMT
 --FILE--
 <?php
 echo strtotime("2006-05-12 13:00:01 America/New_York"), "\n";