diff --git a/lemonldap-ng-portal/t/61-NewLocationWarning-Custom.t b/lemonldap-ng-portal/t/61-NewLocationWarning-Custom.t
index 8d51b9012..cb9a96c33 100644
--- a/lemonldap-ng-portal/t/61-NewLocationWarning-Custom.t
+++ b/lemonldap-ng-portal/t/61-NewLocationWarning-Custom.t
@@ -2,6 +2,10 @@ use Test::More;
 use strict;
 use IO::String;
 
+use POSIX qw(locale_h);
+use locale;
+setlocale(LC_TIME, "C");
+
 BEGIN {
     eval {
         require 't/test-lib.pm';
diff --git a/lemonldap-ng-portal/t/61-NewLocationWarning.t b/lemonldap-ng-portal/t/61-NewLocationWarning.t
index bb1485b9c..106767600 100644
--- a/lemonldap-ng-portal/t/61-NewLocationWarning.t
+++ b/lemonldap-ng-portal/t/61-NewLocationWarning.t
@@ -2,6 +2,10 @@ use Test::More;
 use strict;
 use IO::String;
 
+use POSIX qw(locale_h);
+use locale;
+setlocale(LC_TIME, "C");
+
 BEGIN {
     eval {
         require 't/test-lib.pm';