diff --git a/neutron_lib/plugins/ml2/api.py b/neutron_lib/plugins/ml2/api.py
index d8a7d5fab..36b30122f 100644
--- a/neutron_lib/plugins/ml2/api.py
+++ b/neutron_lib/plugins/ml2/api.py
@@ -23,6 +23,7 @@ NETWORK_TYPE = 'network_type'
 PHYSICAL_NETWORK = 'physical_network'
 SEGMENTATION_ID = 'segmentation_id'
 MTU = 'mtu'
+NETWORK_ID = 'network_id'
 
 # The following keys are used in the binding level dictionaries
 # available via the binding_levels and original_binding_levels