Labour is promising to start a basic commuter rail service between Auckland, Hamilton and Tauranga.

The party made the announcement in Tauranga this morning.

The service is based on a rapid rail blueprint linking Auckland to Tauranga and Hamilton released last week by transport lobby group Greater Auckland.

Labour transport spokesman Michael Wood said the passenger service would run two services each way in the morning and evening between Hamilton and Auckland, and a single return service between Auckland and Tauranga.

He said Greater Auckland was producing a really good long-term transport vision, backed up with detailed investigations. Labour was also relying on work by Environment Waikato on a commuter rail service between Auckland and Hamilton.

Labour also announced it would increase the annual budget for regional roads from $70m to $140m.

Greater Auckland has detailed a three-stage plan to modernise existing regional rail links to use modern-technology tilting trains travelling up to 160km/h on upgraded tracks.

In the first stage, existing trains such as the 96-seater Silver Fern units would run on the current network to build up passenger numbers.

The second stage would be investing in high-speed tilting trains and upgrading the network.

Wood said the initial service to Hamilton and Tauranga would cost $10m, including rolling stock and basic platforms at new stops along the route.

The trains could be the Silver Ferns trains proposed by Greater Auckland or old Auckland diesel locomotives, Wood said.

Labour Party leader Jacinda Ardern made the announcement on the Tauranga waterfront with Wood and local candidates from the Bay of Plenty and Waikato including Tamati Coffey, Jamie Strange and Jan Tinetti.

About 400 gathered for the event - and a glimpse of Ardern who was welcomed with cheers.

Ardern said Tauranga was growing and people needed choices, including how to move around in the "golden triangle" between Auckland, Hamilton and Tauranga. She set out a $20 million plan for the network.

"We will bring back rail passenger transport between Auckland, Hamilton and Tauranga."

Ardern set out other policies, saying National had prioritised the roads of national significance.

"But there are a lot of roads in between."

She said Labour would double a contestable fund for roading improvements for local councils to $280 million.

Ardern also set out a promise for her first 100 Days of in Government - holding a Roading Summit in Wellington for the countries local bodies and transport bodies.

She said it would match the time taken to get to Auckland in a car and only one exchange to get to Auckland airport.

"I remember when we took the train from Morrinsville when I was a kid.

It used to be one of the fundamental ways we got around the country and it should be again."

Ardern said Tauranga was a special place for her and called up a young girl who was a family friend with a homemade 'lets do this' t-shirt.

The Green Party is also making a transport announcement in Auckland at lunchtime today.