Winston Peters favours rail over cutting restrictions for heavy vehicles

New Zealand First leader and Rail Minister Winston Peters has hinted he won't support a law change letting trucks carry more weight during the fuel crisis.

He was adamant: "It's a no brainer, rail is the answer," to the fuel crisis.

The government is considering cutting regulations for heavy vehicles in an effort to save fuel, including easing truck weight limits.

When asked whether he would veto that, Peters said: "Stand back and watch."

He told reporters he was not on board with the idea.

"I'm not for these changes ... these weight limits are put there for good reasons, because of potholes and bridge strength and what have you," he said.

"We're going to make sure we use rail."

Peters' opposition was put to Prime Minister Christopher Luxon, who said his coalition partners' comments were "a bit premature".

The government was considering "all ideas" and associated trade-offs, and nothing had gone to Cabinet, he said.

Resources Minister and New Zealand First deputy Shane Jones agreed.

"The State at the end of the day has to deal with the impact on heavy traffic on our roads, but it's really important that we keep the fuel flowing, and I'm imagining that a fair bit of freight may even go on to KiwiRail."

The Prime Minister added: "I imagine a lot of freight will go on to KiwiRail."

Shifting more freight to rail would not require any regulatory changes - companies can choose to do that if they wish.

KiwiRail publishes its available capacity online and said it anticipated that would be allocated quickly.

Trains were two-and-a-half times more fuel efficient than trucks and there were thousands of wagons available, Peters said.

Peters said the freight industry was using a crisis to get the law changed.

"This ain't the first time the trucking industry's tried this on."

Earlier on Tuesday Transport Minister Chris Bishop said the industry had been advocating for weight limit changes for some time, and the crisis was an opportunity to expedite that work.

Transporting New Zealand chief executive Dom Kalasih told Morning Report loosening the weight restrictions would unlock extra productivity and save several million litres of diesel.

He urged the government to make the changes immediately.

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