The trans-Tasman leaders are well known for their betting relationship, and Prime Minister John Key is putting his money on Julia Gillard to take out the Australian Labor leadership battle today.
The Australian Prime Minister will be pitted against former Prime Minister Kevin Rudd in a leadership ballot.
Asked about the leadership race on Newstalk ZB this morning, Mr Key said Ms Gillard was likely to be the winner.
"But let's see how it goes. I've been around those sort of votes before when at the last moment they change,'' he said.
"The most important thing for a political party is unity. If you can't manage yourself, voters will think you can't manage the country, so whoever wins they've got a big repair job to do with the Australian public.''
Mr Key said the outcome of today's Labor vote was unlikely to affect New Zealand.
"Julia's been great from a New Zealand perspective, we've worked very, very closely with her. Kevin, I think, is committed to the relationship as well, but it was a very busy time when he first became Prime Minister, so, you know, let's see how it goes. On balance, I don't think it would change a lot.''
Trans-Tasman visits between Ms Gillard and Mr Key have frequently included wagers on various sporting events.
In October, Mr Key hosted his weekly press conference in front of an Australian flag as the loser of a bet with Ms Gillard over the outcome of the NRL grand final between the Warriors and the Manly Sea Eagles.
However, a week later Mr Key got his own back following the All Blacks' Rugby World Cup triumph over the Wallabies, which meant Ms Gillard was forced to eat a New Zealand apple while describing its attributes in detail.
