Air New Zealand has extended a freeze on international flight bookings until the end of next week.

The airline put a hold on new bookings in early July to help the government organise quarantine for incoming passengers and extended it to 29 July.

This morning it confirmed the freeze has been extended until 9 August.

It said some customers might need to be moved to other flights, and the airline would contact any affected customers.

Air NZ signalled in early July that it might extend the freeze.

At the time, Air New Zealand chief executive Greg Foran told RNZ's Checkpoint he agreed to the three-week booking freeze on an "ethical" basis.

It had been a simple decision to provide the right support to the government by not putting pressure on managed isolation capacity, he said.

The minister responsible for managed isolation, Megan Woods, said at the time that "Our number one priority is stopping the virus at the border, so everyone must to go into quarantine or managed isolation. The government is also talking to other airlines about managing flows.

"The last thing we need are hastily set up facilities to meet demand, so we must have a manageable number of fit-for-purpose, safe facilities that do the job of stopping Covid at the border."