Calls for more clarity on border re-opening plans are growing, as Auckland Airport warns many airlines will not fly long-haul routes here without a timetable for the end of self-isolation.

Interim chief executive Mary-Liz Tuck said while yesterday's border reopening announcement was welcome news for Kiwis wanting to return home and a "positive first step" for the aviation industry, airlines want to know now what the trigger points will be for when self-isolation requirements will be removed for travellers.

The airport had spoken to 10 airlines over the past 24 hours, and the feedback had been consistent.

Without clear guidance around the trigger points or a date for self-isolation ending, they would not be able to attract meaningful traveller volumes needed to sustain long-haul flights to and from New Zealand, she said.

"Airlines are looking to deploy their fleets where they can get consistent, stable passenger volumes, and they are focusing on overseas markets that have communicated a clear path out of border restrictions, following a surge of Omicron in the community."

Currently 12 airlines fly to 22 international destinations from Auckland Airport, compared to 29 airlines connecting to 43 international destinations just before the pandemic hit.

International flight movements in 2021 at Auckland Airport were roughly the same as around 35 years ago, with international passenger volumes down by 96 per cent since December 2019.

Just one daily wide-body flight to New Zealand a year carries $500 million worth of freight.

"For a trade-dependent nation like ours, that reduction in competition and connectivity will not only hit passengers in the pocket but also businesses who rely on air freight as a critical part of their supply chain," Tuck said.

International airlines are calling for a clear plan around the removal of self-isolation as a requirement for returning travellers, saying they need more certainty so they can plan to return flying here.

"Our airline customers have also been very clear that they need to know now when self-isolation will end before they can plan to resume flying here."

Mary-Liz Tuck is Auckland Airport's interim chief executive. Photo / Supplied

Under staged re-opening plans, New Zealanders returning from Australia can skip MIQ from the end of the month and those from the rest of the world can avoid MIQ from mid-March. But they are required to self-isolate for up to 10 days.

Other nationalities can enter in stages throughout the year and the country fully reopens to tourists from October, but there are no guidelines yet on isolation requirements then.

Airlines say the evidence is that border restrictions are no longer a useful tool once Omicron is established in a community, and that vaccinated and tested travellers will present very little risk to New Zealand once this takes place.

"They have shared with us that overseas markets with continued self-isolation requirements experienced passenger demand that hovered at around 5 per cent to 10 per cent of pre-Covid levels," Tuck said.

Analysis by Auckland Airport has shown that a continued isolation requirement will have a significant impact on New Zealand's travel market.

Demand from the Australia visitor market (excluding New Zealanders visiting friends and family) is estimated at just 7 per cent of 2019 levels if self-isolation remains in place as a requirement.