diff --git a/vmware_nsx/nsxlib/v3/resources.py b/vmware_nsx/nsxlib/v3/resources.py
index ace377e32f..a19b569633 100644
--- a/vmware_nsx/nsxlib/v3/resources.py
+++ b/vmware_nsx/nsxlib/v3/resources.py
@@ -240,8 +240,8 @@ class LogicalPort(AbstractRESTResource):
                 })
             body['switching_profile_ids'] = profiles
 
-        if attachment:
-            body['attachment'] = attachment
+        # Note that attachment could be None, meaning reset it.
+        body['attachment'] = attachment
 
         return body