Clare represents the western Sydney seat of Blaxland; Morrison holds Cook, which covers the Sutherland shire. The pair hit it off during television debates and decided to do something to improve relations between their communities.

In 2009 they did the Kokoda Trail together. Clare brought along four Muslim kids from Punchbowl; Morrison brought four surf life savers from Cronulla.

They have since trekked in Borneo and Papua New Guinea. They've become friends as well as political adversaries.

"You can disagree vehemently about what needs to be done to make Australia a better country and still be mates," Clare says.

"We don't always see eye to eye but when you're walking through the mud and sweat of Kokoda for eight days, you see another side of people and you develop friendships."

Like most things in politics, the question of friendships across the partisan divide is hotly debated.

"There are not many great friendships across the parties," says Queensland Liberal MP Wyatt Roy.

"It's frustrating there's not more of it but that's the difficult reality."

It's one thing to share a laugh, he says. Genuine friendship is something else.

Fellow Queensland MP Ewen Jones says many Labor politcians are good people but adds: "I don't think many on the other side would stop to help me if I was getting picked on in a pub."

Liberal MP Craig Laundy, who holds the marginal western Sydney seat of Reid, tells a different story. "You can definitely have friendships across politics that go beyond respect," he says.

Laundy admits he's a "weird kettle of fish in the Liberal Party". He's a publican from a Labor family – a different background to the many politicians who rose up through student politics and political staffing.

Jason Clare is Laundy's​ best friend in politics. The pair met each other when Clare was campaigning in his electorate, where Laundy's​ father owns several pubs.

"We have a very similar sense of humour and we enjoy a beer. We go out for dinner with our wives. He'll be a mate till the day I die."

It's a side of political life Laundy​ wishes the public saw more of.

"We go into question time and we're very combative for an hour and 15 minutes of the day. But behind the scenes we are working on a lot of projects together like parliamentary friendship groups and committees. It's very bipartisan."

Labor MP Ed Husic and Assistant Treasurer Josh Frydenberg​ are known as the "ebony and ivory" of Australian politics. As well as coming from opposing parties they have different religious backgrounds: Frydenberg is Jewish while Husic​ was the first Australian MP to swear his oath of office on the Koran. The good friends have shared meals at each others' homes.

Frydenberg​ says he was inspired by the example of Robert Menzies, who believed politics should be a battle of ideas and not warring personalities.

To the consternation of some in his party, Menzies formed strong friendships with Labor figures John Cain and John Curtin.

Frydenberg​ says having friends from the other side of politics "helps you to maintain your perspective in what can be a really hot-house atmosphere".

Husic​ believes younger politicians are better at looking beyond party differences to forge friendships.

"I have seen people on my side who can't bring themselves to take to Libs and the other way around," he says.

"I don't think anyone in the community is putting their hand up to see more division in Australian politics."

Nationals Senator Bridget McKenzie has become close to Labor MP Joanne Ryan through co-captaining the parliamentary netball team. Liberal MP Kelly O'Dwyer​ became friends with Labor's Kate Ellis and Amanda Rishworth, who were due to give birth on a similar date to her this year.

"I'm really happy for us to be able to share any information or tips that may make things just a little bit smoother along the way," Ellis said earlier this year.

Labor's Andrew Leigh, who gets along well with Communications Minister Malcolm Turnbull, says many cross-party friends prefer to keep it quiet.

"There's more of it than you would think, but the brutal partisanship of politics can be unforgiving for people who are seen to have friendships across party lines," he says.

"It's probably not a good career move for a Liberal backbencher to have a friend on the other side of politics."

Politicians could hardly come more tribal than Christopher Pyne and Anthony Albanese​. Yet the pair have become famous for their friendly rapport during their regular Today show appearances.

"Some people take politics terribly personally and take the game off the field. We don't," Pyne says.

The pair were in charge of their party's parliamentary tactics during the "toxic" hung Parliament period and realised they share a cheeky sense of humour.

But they're not swapping squash racquets or acting as godfathers to each other's children. Not yet.

"When we've both left politics I think we'll be friends," Pyne says.