A gay marriage rally on the steps of the Victoria State Parliament building. Picture: Jake Nowakowski Source: News Corp Australia

As his own backbenchers prepare to introduce a cross-party Bill on marriage equality, the Prime Minister has made clear the economy and national security are his priorities — not marriage reform.

But a senior Liberal MP told Sky News this morning that the move could imperil Mr Abbott’s leadership.

If Mr Abbott did not allow party members a conscience vote on the issue, “he would be back to where he was in January”, Sky quoted the source as saying.

The Prime Minister’s leadership hung by a thread at the beginning of this year, but a spill motion in Febraury was ultimately unsuccessful and no other contender declared their intention.

The same-sex marriage bill, drafted by Liberals Warren Ensch and Teresa Gambaro and seconded by Labor’s Terri Butler, will not be brought on for debate, or even discussed in the Coalition party rooms.

Mr Abbott reminded his Coalition MPs a private member’s Bill would not be discussed in the joint party room unless it was to be voted on in the Parliament.

“It is rare for a private member’s Bill to be voted on and any Bill would be subject to the usual process,” a spokesman for Mr Abbott said yesterday.

“The Prime Minister’s position remains the same as it has always been and he supports the current policy that marriage is between a man and a woman.

“The government’s priority is strong economic management and keeping Australians safe.”

Mr Abbott reiterated those statements today, saying in his 21 years in Parliament “there have only been two or three occasions when a Private Members’ Bill has come on fgor debate and vote.”

But Labor’s Penny Wong layer: contradicted Mr Abbott on Twitter:

SAME SEX MARRIAGE A ‘PANDORA’S BOX’: ABETZ

Opposing same-sex marriage ... the government’s leader in the Senate, Eric Abetz. Picture: Kym Smith Source: News Corp Australia

Tasmanian Senator Eric Abetz has championed Mr Abbott’s position, warning on Sky News this morning that same sex marriage reform could pave the way for the demand for legal recognition of polyamorous relationships.

“If you undo the definition you open up a Pandora’s box,” he said.

Senator Abetz suggested that champions of same-sex marriage had no place on the Coaltion’s front bench, and argued that Australia should not adopt same-sex marriage because our Asian neighbours have not adopted it.

“Here we are in the Asian century, what other Asian country has legalised gay marriage?” Senator Abetz asked.

Liberal frontbencher Concetta Fierravanti-Wells is another MP rallying against amending the Marriage Act.

“Any change of this magnitude requires appropriate consultation and not the sort of ambush approach some of my colleagues have chosen to take,” she told ABC radio on Thursday.

THE PUSH FOR CHANGE WITHIN LIBERAL RANKS

It was revealed yesterday afternoon that there were plans afoot for an August 18 showdown to allow Coalition MPs a conscience vote on changes to the Marriage Act.

Marriage equality campaigners want to harness momentum on the issue following endorsement from the Irish referendum and the ruling by the US Supreme Court that same-sex marriage was constitutional in all states.

Mr Entsch and Ms Gambaro will take their proposed legislation to their party room, with an appeal for a conscience vote on the matter.

They are expected to be backed by co-sponsorship from House of Representatives independents Cathy McGowan and Andrew Wilkie.

Labor MPs Terri Butler and Laurie Ferguson will be the Labor flank backing the legislation.

Discussions on cross-party legislation were held last week, the final sitting week before the winter break.

Labor leader Bill Shorten welcomed what he called “this sign of progress” and backed a free vote for all MPs. “I hope it means Tony Abbott will finally grant Liberal MPs a free vote on the legislation. As I’ve consistently said, it’s the outcome that is important here, not whose name is on the bill,” the Opposition leader said.

“Like millions of Australians, my first and only hope here is that we can make marriage equality a reality.”

Teresa Gambaro will also take the Bill to the party room. Source: News Corp Australia

Coalition MP Warren Entsch is expected to introduce the Bill. Source: News Corp Australia

The news comes just days after the US Supreme Court voted to allow gay marriage. As President Barack Obama hailed the landmark decision as a “victory for America”, Mr Abbott said his views on gay marriage “hadn’t changed”.

“Obviously there is a community debate going on, I have views on the subject which are pretty well-known and they haven’t changed,” the PM said in Melbourne on Saturday.

Education Minister Christopher Pyne said: “There appears to be growing momentum worldwide towards marriage equality and our parliament will deal with it at the appropriate time in the appropriate way.”

Labor and the Greens have backed growing calls for marriage equality in Australia, with Mr Shorten and Deputy Opposition Leader Tanya Plibersek supporting calls for action in Parliament.

“If we want the whole parliament to own it, I extend the invitation again to Mr Abbott that a Liberal can move it,” Mr Shorten said after the US vote. “For us, it’s not about who moves it and who seconds it. For me, it’s about the outcome.”

The Prime Minister warned Mr Shorten after his May bid to introduce same-sex marriage not to play party politics with the issue. “If our Parliament were to make a big decision on a matter such as this, it ought to be owned by the Parliament and not by any particular party,” Mr Abbott said.

Jim Obergefell, the plaintiff in the Obergefell v. Hodges case that legalised same sex marriage in the US, after the ruling. Source: AP

Former prime minister Kevin Rudd also hailed the decision in the US and said on Twitter that it was “time now for Oz to act”. The Greens said the US ruling was the loudest call yet for marriage equality in Australia.

This week, Facebook users across the world have been making their profile pictures rainbow-coloured to show their support for same-sex marriage. Australians rallied in support of marriage equality in Brisbane’s bayside over the weekend, and hundreds protested on the steps of Victoria’s parliament two weeks ago.

Senator Penny Wong told the Melbourne crowd the marriage equality movement was “unstoppable” and that it was disappointing that Australia had fallen behind every other English-speaking country.

But some remain opposed to same-sex marriage, with the Australian Christian Lobby and the Australian Marriage Forum criticising the US decision.

“The US Supreme Court has ushered in a new era of civil discord with its politically activist and morally reckless ruling on homosexual ‘marriage’,” Australian Marriage Forum president Dr David van Gend said in a statement. “We must not let that happen here.”

Nationals deputy leader Barnaby Joyce has also said he does not believe marriage should be redefined.