diff --git a/requirements.txt b/requirements.txt
index 383a5d9467..af54f6cc5b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -38,7 +38,7 @@ python-novaclient>=2.18.0
 python-saharaclient>=0.7.6
 python-swiftclient>=2.2.0
 python-troveclient>=1.0.7
-pytz
+pytz>=2013.6
 PyYAML>=3.1.0
 six>=1.7.0
 XStatic>=1.0.0  # MIT License