Air New Zealand has entered in to a new strategic alliance with Qantas.
The agreement was closely guarded until being announced at Sydney Airport on Friday morning.
The new deal will mean Air NZ passengers booking flights into Australia can fly on Qantas domestic flights on an Air NZ ticket, and Qantas passengers can do the same within New Zealand on the Air NZ network with a Qantas ticket.
For example, if you wanted to fly from Auckland to Alice Springs you could book this directly with Air NZ even though you'll be flying on a Qantas flight from Sydney to Alice Springs.
Qantas CEO Alan Joyce said the airlines have a lot of history.
"Our relationship together goes back 80 years. We've been partners at various stages over that time and we have a lot of respect for them as a competitor."
The agreement won't apply to trans-Tasman travel, and Qantas will still sell tickets for JetStar in New Zealand.
The move will hurt Qantas' main rival Virgin Australia, which until recently was not only in a similar partnership with Air NZ but was partially owned by our national airline.
Air NZ and Virgin Australia had been working in partnership since 2010. Air NZ sold its stake in 2016 and pulled out of the partnership entirely in April.
The deal is also unique given Air NZ and Qantas are fierce competitors on trans-Tasman and international routes, and each are aligned with different global alliances - Qantas is part of One World and Air NZ is a member of the Star Alliance.