Getting around Auckland could be difficult today, with the signing of the TPP coinciding with a bus driver strike.

Drivers employed by NZ Bus will be taking industrial action between 9am and 2.30pm.

Auckland Transport bus manager Brendon Main said Metrolink, Go West, North Star and Waka Pacific services will be affected.

"We are asking for the public's patience tomorrow, obviously the timing isn't ideal for this happening and we're trying to provide as good a service as we can."

He said school buses, trains, ferries and other bus services will operate as normal.

Mr Main said limited services may operate on some routes.

"We are operating a skeleton service on some of the main bus corridors during that time, we're using buses from bus other operators around Auckland."

InterLink services will run as normal and OuterLink services will run every half hour rather than every 15 minutes.