diff --git a/src/tree_data_common.c b/src/tree_data_common.c
index d97f643ea..6363e98cc 100644
--- a/src/tree_data_common.c
+++ b/src/tree_data_common.c
@@ -1620,30 +1620,12 @@ ly_time_tz_offset(void)
     return ly_time_tz_offset_at(time(NULL));
 }
 
-/**
- * @brief Call tzset() if not already called by this process.
- */
-static void
-ly_tzset_once(void)
-{
-    static int ly_tzset_called = 0;
-
-    if (ly_tzset_called) {
-        return;
-    }
-    tzset();
-    ly_tzset_called = 1;
-}
-
 LIBYANG_API_DEF int
 ly_time_tz_offset_at(time_t time)
 {
     struct tm tm_local, tm_utc;
     int result = 0;
 
-    /* init timezone */
-    ly_tzset_once();
-
     /* get local and UTC time */
     localtime_r(&time, &tm_local);
     gmtime_r(&time, &tm_utc);
@@ -1791,9 +1773,6 @@ ly_time_time2str(time_t time, const char *fractions_s, char **str)
 
     LY_CHECK_ARG_RET(NULL, str, LY_EINVAL);
 
-    /* init timezone */
-    ly_tzset_once();
-
     /* convert */
     if (!localtime_r(&time, &tm)) {
         return LY_ESYS;
diff --git a/tests/utests/utests.h b/tests/utests/utests.h
index b1f72cc42..a81a34d8b 100644
--- a/tests/utests/utests.h
+++ b/tests/utests/utests.h
@@ -1326,6 +1326,8 @@ utest_setup(void **state)
 
     /* set CET */
     setenv("TZ", "CET+02:00", 1);
+    /* call tzset explicitly, to update the tzname, timezone and daylight global variables */
+    tzset();
 
     return 0;
 }