diff --git a/utils/os_client.py b/utils/os_client.py
index 12aad1b..8ef55de 100644
--- a/utils/os_client.py
+++ b/utils/os_client.py
@@ -376,12 +376,21 @@
 
     def create_network(self, tenant_id):
         net_name = "spt-test-net-{}".format(random.randrange(100, 999))
+        config = utils.get_configuration()
+        mtu = config.get('custom_mtu') or 'default'
         net_body = {
             'network': {
                 'name': net_name,
                 'tenant_id': tenant_id
             }
         }
+        if mtu != 'default':
+            try:
+                net_body['network']['mtu'] = int(mtu)
+            except ValueError as e:
+                raise ValueError("MTU value '{}' is not correct. "
+                                 "Must be an integer at 'custom_mtu' in "
+                                 "global_config.yaml.\n{}".format(mtu, e))
         net = self.os_clients.network.create_network(net_body)['network']
         logger.info("Created internal network {}".format(net_name))
         return net