'Not ideal': NZ Defence Force plane lets down PM Luxon

Mr Luxon is attending his first international gathering of leaders on Tuesday after accepting an invitation from Australian Prime Minister Anthony Albanese.

However, his plans to take a NZDF 757 from Wellington airport went awry when maintenance issues grounded the plane.

Radio NZ reported Mr Luxon scrambled to get from the Rongotai defence force base to Wellington airport, where he caught a flight to Auckland before transferring to a trans-Tasman flight to the Victorian capital.

The delay means the Kiwi prime minister will miss a few of his bilateral meetings at the summit, where he is meeting southeast Asian leaders back-to-back all day.

"It's not ideal," acting National leader and Finance Minister Nicola Willis said.

With each breakdown, there are calls to bring forward a scheduled replacement of the 757s, which is due later this decade.

Ms Willis, who is enacting broad cuts to the public service, suggested it wouldn't be happening under her fiscally tight watch.

"The number one priority isn't getting politicians to meetings. The number one priority is working well with our partners internationally to ensure we can defend our country and our interests," she said.

Defence Minister Judith Collins said the NZDF does "an enormously good job with very, very old kit".

"Essentially you're talking about classic cars, but it's planes," she said.

"It's an engineering issue ... it's embarrassing, it's difficult. But every time we this happens we talk about the need for alternatives and every time we look at it it's so expensive and frankly we're in a cost of living crisis."

Opposition leader Chris Hipkins said Labour would not argue with the government if it wanted to replace the craft ahead of time.

"If they decide to upgrade the 757s they'd have my support," he said.

On Tuesday morning, a number of accompanying staff and media were left at Rongotai base, hoping to attend the Melbourne talks if the plane is deemed flight-worthy.

They remained at the base at 11am, five hours after the scheduled departure time, with further investigations needed before attempting to fly on Tuesday afternoon.

The recurrent faults, which Mr Luxon previously labelled "incredibly embarrassing", are an ongoing issue for New Zealand leaders.

Unlike the Australian prime minister, who has a similar plane at his disposal, New Zealand leaders must borrow the plane from NZDF duty when they seek to undertake international travel.

The unreliability of the planes has led to prime ministers and ministerial delegations being stranded in various places around the world, including Melbourne, Townsville, Vanuatu, Solomon Islands and Washington DC.

Australian Associated Press