diff --git a/nova/api/openstack/servers.py b/nova/api/openstack/servers.py
index 18eef246455..c45e7510c56 100644
--- a/nova/api/openstack/servers.py
+++ b/nova/api/openstack/servers.py
@@ -664,6 +664,9 @@ def _action_change_password(self, input_dict, req, id):
     def _action_confirm_resize(self, input_dict, req, id):
         try:
             self.compute_api.confirm_resize(req.environ['nova.context'], id)
+        except exception.MigrationNotFound:
+            msg = _("Instance has not been resized.")
+            raise exc.HTTPBadRequest(explanation=msg)
         except Exception, e:
             LOG.exception(_("Error in confirm-resize %s"), e)
             raise exc.HTTPBadRequest()
@@ -672,6 +675,9 @@ def _action_confirm_resize(self, input_dict, req, id):
     def _action_revert_resize(self, input_dict, req, id):
         try:
             self.compute_api.revert_resize(req.environ['nova.context'], id)
+        except exception.MigrationNotFound:
+            msg = _("Instance has not been resized.")
+            raise exc.HTTPBadRequest(explanation=msg)
         except Exception, e:
             LOG.exception(_("Error in revert-resize %s"), e)
             raise exc.HTTPBadRequest()
diff --git a/nova/tests/api/openstack/test_server_actions.py b/nova/tests/api/openstack/test_server_actions.py
index ae40b3c9516..b6852093eca 100644
--- a/nova/tests/api/openstack/test_server_actions.py
+++ b/nova/tests/api/openstack/test_server_actions.py
@@ -272,6 +272,20 @@ def confirm_resize_mock(*args):
         res = req.get_response(fakes.wsgi_app())
         self.assertEqual(res.status_int, 400)
 
+    def test_confirm_resize_migration_not_found(self):
+        req = self.webreq('/1/action', 'POST', dict(confirmResize=None))
+
+        def confirm_resize_mock(*args):
+            raise exception.MigrationNotFoundByStatus(instance_id=1,
+                                                      status='finished')
+
+        self.stubs.Set(nova.compute.api.API,
+                       'confirm_resize',
+                       confirm_resize_mock)
+
+        res = req.get_response(fakes.wsgi_app())
+        self.assertEqual(res.status_int, 400)
+
     def test_revert_resize_server(self):
         req = self.webreq('/1/action', 'POST', dict(revertResize=None))
 
@@ -299,6 +313,20 @@ def revert_resize_mock(*args):
         res = req.get_response(fakes.wsgi_app())
         self.assertEqual(res.status_int, 400)
 
+    def test_revert_resize_migration_not_found(self):
+        req = self.webreq('/1/action', 'POST', dict(revertResize=None))
+
+        def revert_resize_mock(*args):
+            raise exception.MigrationNotFoundByStatus(instance_id=1,
+                                                      status='finished')
+
+        self.stubs.Set(nova.compute.api.API,
+                       'revert_resize',
+                       revert_resize_mock)
+
+        res = req.get_response(fakes.wsgi_app())
+        self.assertEqual(res.status_int, 400)
+
     def test_create_backup(self):
         """The happy path for creating backups"""
         self.flags(allow_admin_api=True)