diff --git a/requirements.txt b/requirements.txt
index 3338cbd6..354353a7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@
 
 pbr>=2.0.0 # Apache-2.0
 # Horizon Core Requirements
-Babel>=2.3.4 # BSD
+Babel!=2.4.0,>=2.3.4 # BSD
 Django<1.9,>=1.8 # BSD
 django-compressor>=2.0 # MIT
 django-openstack-auth>=3.1.0 # Apache-2.0