Why an Air New Zealand plane made an unscheduled detour in Port Moresby, Papua New Guinea

Surprised passengers on an international commercial flight were hit with a bizarre delay after their plane was re-routed to pick up New Zealand Prime Minister Cristopher Luxon.

The Air New Zealand flight collected the PM after he became stranded in Papua New Guinea when the government aircraft he was due to fly on broke down on Sunday.

He and a group of 50 prominent business leaders had been en route to Tokyo for a summit with Japanese Prime Minister Fumio Kishida when the Royal New Zealand Defence Force plane they were travelling in stopped in Port Moresby to refuel.

But the 30-year-old Boeing 757 was unable to continue the journey due to a fuse issue.

Mr Luxon and three staff arrived in Tokyo on schedule thanks to the commercial flight, while others in the group spent the night in Port Moresby.

Of the stranded travelling group, two had ties to Air New Zealand - airline boss Greg Foran and Mr Luxon himself.

The Prime Minister previously spent seven years at the helm of the airline prior to being elected to office in 2023. 

Despite the stroke of good luck, the country's defence minister who was also briefly stranded, Judith Collins, told Newstalk ZB the situation was 'embarrassing'.

'We have a very old aircraft and we are expecting it to perform like brand new out of the box and that's simply not going to happen,' she told the radio station.

'No PM wants to spend an awful amount of money on something that's seen as nice to have by some people.'

Mr Foran said the cost of having one of his own commercial flights diverted to pick up the group was a matter for another day.

'Let’s get everyone there, we’ll worry about what we’re going to do financially when we get everyone there,' he told the media. 

It's the latest airline breakdown for Mr Luxon after he was forced make a last-minute change to a commercial flight to attend the Asean summit in Melbourne in March.

Former Prime Minister Jacinda Ardern had similar trips to Washington and Australia delayed by issues with planes part of the country's defence force.

The string of issues has spurred on debate among New Zealand politicians as to whether the country can afford to replace them.

A new fleet is due to be introduced by 2028, however a defence capability review due later this month may see it brought forward to avoid the embarrassing delays.