diff --git a/requirements.txt b/requirements.txt
index 9b44113a20..e4054d2ec8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,7 @@ pbr!=2.1.0,>=2.0.0 # Apache-2.0
 six>=1.9.0 # MIT
 
 Babel!=2.4.0,>=2.3.4 # BSD
-cliff>=2.3.0 # Apache-2.0
+cliff>=2.6.0 # Apache-2.0
 keystoneauth1>=2.18.0 # Apache-2.0
 openstacksdk>=0.9.14 # Apache-2.0
 osc-lib>=1.2.0 # Apache-2.0