diff --git a/tests/ztimer_msg/Makefile b/tests/ztimer_msg/Makefile
index 7289b23ccd..247bbc2030 100644
--- a/tests/ztimer_msg/Makefile
+++ b/tests/ztimer_msg/Makefile
@@ -2,10 +2,10 @@ include ../Makefile.tests_common
 
 USEMODULE += ztimer_usec
 
-# uncomment this to test using ztimer msec on rtt
-#USEMODULE += ztimer_msec ztimer_periph_rtt
+# uncomment this to test using ztimer msec
+#USEMODULE += ztimer_msec
 
-# uncomment this to test using ztimer sec on rtc
-#USEMODULE += ztimer_sec ztimer_periph_rtc
+# uncomment this to test using ztimer sec
+#USEMODULE += ztimer_sec
 
 include $(RIOTBASE)/Makefile.include
diff --git a/tests/ztimer_underflow/Makefile b/tests/ztimer_underflow/Makefile
index 2a44cfd641..88ca9a1bb7 100644
--- a/tests/ztimer_underflow/Makefile
+++ b/tests/ztimer_underflow/Makefile
@@ -6,7 +6,6 @@ USEMODULE += ztimer
 USEMODULE += ztimer_usec
 ifeq ($(TEST_ZTIMER_CLOCK), ZTIMER_MSEC)
   USEMODULE += ztimer_msec
-  USEMODULE += ztimer_periph_rtt
 	# the same for Kconfig
   ifeq (1,$(TEST_KCONFIG))
     KCONFIG_ADD_CONFIG += $(APPDIR)/app.config.msec.test
@@ -14,7 +13,6 @@ ifeq ($(TEST_ZTIMER_CLOCK), ZTIMER_MSEC)
 endif
 ifeq ($(TEST_ZTIMER_CLOCK), ZTIMER_SEC)
   USEMODULE += ztimer_sec
-  USEMODULE += ztimer_periph_rtc
 endif
 
 CFLAGS += -DTEST_ZTIMER_CLOCK=$(TEST_ZTIMER_CLOCK)