diff --git a/neutron/agent/l3_agent.py b/neutron/agent/l3_agent.py
index 8ddbd75756..aa7f7b782f 100644
--- a/neutron/agent/l3_agent.py
+++ b/neutron/agent/l3_agent.py
@@ -645,17 +645,11 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback, manager.Manager):
 
         self.driver.init_l3(interface_name, [ex_gw_port['ip_cidr']],
                             namespace=ri.ns_name,
+                            gateway=ex_gw_port['subnet'].get('gateway_ip'),
                             preserve_ips=preserve_ips)
         ip_address = ex_gw_port['ip_cidr'].split('/')[0]
         self._send_gratuitous_arp_packet(ri, interface_name, ip_address)
 
-        gw_ip = ex_gw_port['subnet']['gateway_ip']
-        if ex_gw_port['subnet']['gateway_ip']:
-            cmd = ['route', 'add', 'default', 'gw', gw_ip]
-            ip_wrapper = ip_lib.IPWrapper(self.root_helper,
-                                          namespace=ri.ns_name)
-            ip_wrapper.netns.execute(cmd, check_exit_code=False)
-
     def external_gateway_removed(self, ri, ex_gw_port,
                                  interface_name, internal_cidrs):
 
diff --git a/neutron/agent/linux/interface.py b/neutron/agent/linux/interface.py
index 946de18fdb..c3a68bbb30 100644
--- a/neutron/agent/linux/interface.py
+++ b/neutron/agent/linux/interface.py
@@ -72,7 +72,7 @@ class LinuxInterfaceDriver(object):
         self.root_helper = config.get_root_helper(conf)
 
     def init_l3(self, device_name, ip_cidrs, namespace=None,
-                preserve_ips=[]):
+                preserve_ips=[], gateway=None):
         """Set the L3 settings for the interface using data from the port.
 
         ip_cidrs: list of 'X.X.X.X/YY' strings
@@ -105,6 +105,9 @@ class LinuxInterfaceDriver(object):
             if ip_cidr not in preserve_ips:
                 device.addr.delete(ip_version, ip_cidr)
 
+        if gateway:
+            device.route.add_gateway(gateway)
+
     def check_bridge_exists(self, bridge):
         if not ip_lib.device_exists(bridge):
             raise exceptions.BridgeDoesNotExist(bridge=bridge)
diff --git a/neutron/tests/unit/test_l3_agent.py b/neutron/tests/unit/test_l3_agent.py
index 8f936d4bcc..20f3e42c79 100644
--- a/neutron/tests/unit/test_l3_agent.py
+++ b/neutron/tests/unit/test_l3_agent.py
@@ -178,7 +178,8 @@ class TestBasicRouterOperations(base.BaseTestCase):
             self.send_arp.assert_called_once_with(ri, interface_name,
                                                   '20.0.0.30')
             kwargs = {'preserve_ips': ['192.168.1.34/32'],
-                      'namespace': 'qrouter-' + router_id}
+                      'namespace': 'qrouter-' + router_id,
+                      'gateway': '20.0.0.1'}
             self.mock_driver.init_l3.assert_called_with(interface_name,
                                                         ['20.0.0.30/24'],
                                                         **kwargs)