The prime minister has caught a commercial flight after the Defence Force plane taking him to Japan blew two fuses in Papua New Guinea.

Christopher Luxon was en route to Tokyo with a business delegation.

He was only supposed to be in Port Moresby for 90 minutes on Sunday while the Boeing 757 was refuelled.

After an hour's delay, a Defence Force spokesperson confirmed the aircraft had blown not one, but two, fuses.

Luxon caught a commercial flight out of Papua New Guinea and would now fly to Tokyo via Hong Kong.

The business and media delegations travelling with him had been given chips and beer in a terminal lounge in Port Moresby.

Crew were working on the plane, and media were told that if the fault could not be fixed, they would be flown back to Australia

Luxon was also forced to fly commercial in March, when the plane broke down before leaving the tarmac in Wellington.