diff --git a/workspace_tools/synch.py b/workspace_tools/synch.py
index a49f738041..03cfb6776b 100644
--- a/workspace_tools/synch.py
+++ b/workspace_tools/synch.py
@@ -311,7 +311,7 @@ def update_dependencies(repositories):
 
 
 def update_mbed():
-    update_repo("mbed", [join(BUILD_DIR, "mbed")])
+    update_repo("mbed", [join(BUILD_DIR, "mbed")], None)
 
 def do_sync(options):
     global push_remote, quiet, commit_msg, changed