diff --git a/tempest/common/waiters.py b/tempest/common/waiters.py
index 073481c..9d307ee 100644
--- a/tempest/common/waiters.py
+++ b/tempest/common/waiters.py
@@ -53,9 +53,7 @@
                     return
                 # NOTE(afazekas): The instance is in "ready for action state"
                 # when no task in progress
-                # NOTE(afazekas): Converted to string because of the XML
-                # responses
-                if str(task_state) == "None":
+                if task_state is None:
                     # without state api extension 3 sec usually enough
                     time.sleep(CONF.compute.ready_wait)
                     return