diff --git a/manila/api/v1/security_service.py b/manila/api/v1/security_service.py
index 2ad26cc581..dca6add24a 100644
--- a/manila/api/v1/security_service.py
+++ b/manila/api/v1/security_service.py
@@ -66,9 +66,9 @@ class SecurityServiceController(wsgi.Controller):
         share_nets = db.share_network_get_all_by_security_service(
             context, id)
         if share_nets:
-            # Cannot delete security service
-            # if it is assigned to share networks
-            raise exc.HTTPForbidden()
+            msg = _("Cannot delete security service. It is "
+                    "assigned to share network(s)")
+            raise exc.HTTPForbidden(explanation=msg)
         policy.check_policy(context, RESOURCE_NAME,
                             'delete', security_service)
         db.security_service_delete(context, id)