Air New Zealand and Indonesia's Garuda airline face hefty multi-million fines after being found to have participated in a cartel to fix the prices of cargo flights.

The Full Court of the Federal Court on Monday upheld an appeal by the Australian Competition and Consumer Commission after finding the two airlines had engaged in a cartel.

Air New Zealand faces a heft fine for participating in a cartel to fix the prices of cargo flights.

It could prove to be an expensive time for the Australian Securities Exchange-listed Air New Zealand.

Air NZ on Monday stumped up $131.2 million in a loan to Virgin Australia as part of a lending deal provided by Virgin's largest shareholders.