diff --git a/neutron/extensions/l3_ext_gw_mode.py b/neutron/extensions/l3_ext_gw_mode.py
index a9726a18c29..530279d0119 100644
--- a/neutron/extensions/l3_ext_gw_mode.py
+++ b/neutron/extensions/l3_ext_gw_mode.py
@@ -32,7 +32,7 @@ EXTENDED_ATTRIBUTES_2_0 = {
                                    'convert_to': attrs.convert_to_boolean},
                    'external_fixed_ips': {
                        'convert_list_to': attrs.convert_kvp_list_to_dict,
-                       'validate': {'type:fixed_ips': None},
+                       'type:fixed_ips': None,
                        'default': None,
                        'required': False}
                    }
diff --git a/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py b/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
index 28577f57112..e2229f86537 100644
--- a/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
+++ b/neutron/tests/unit/extensions/test_l3_ext_gw_mode.py
@@ -16,6 +16,7 @@
 
 import mock
 from oslo_config import cfg
+from oslo_serialization import jsonutils
 from oslo_utils import uuidutils
 import testscenarios
 from webob import exc
@@ -388,6 +389,24 @@ class ExtGwModeIntTestCase(test_db_base_plugin_v2.NeutronDbPluginV2TestCase,
                             expected_code=expected_code,
                             neutron_context=neutron_context)
 
+    def test_router_create_with_gwinfo_invalid_ext_ip(self):
+        with self.subnet() as s:
+            self._set_net_external(s['subnet']['network_id'])
+            ext_info = {
+                'network_id': s['subnet']['network_id'],
+                'external_fixed_ips': [{'ip_address': '10.0.0.'}]
+            }
+            error_code = exc.HTTPBadRequest.code
+            res = self._create_router(
+                self.fmt, _uuid(), arg_list=('external_gateway_info',),
+                external_gateway_info=ext_info,
+                expected_code=error_code
+            )
+            msg = ("Invalid input for external_gateway_info. "
+                   "Reason: '10.0.0.' is not a valid IP address.")
+            body = jsonutils.loads(res.body)
+            self.assertEqual(msg, body['NeutronError']['message'])
+
     def test_router_create_show_no_ext_gwinfo(self):
         name = 'router1'
         tenant_id = _uuid()