Malcolm Turnbull has moved to head off a push by his backbench to legalise same-sex marriage before the next election using a private members bill.

While leaving open the possibility of taking a different policy to the next election, such as a free vote in Parliament , Mr Turnbull said the Coalition would not be supporting any vote for same-sex marriage before the election unless there was a plebiscite first.

“The next election is two years away and we will examine our policy in the lead up to the next election, but we made a commitment at the last election that we would have a plebiscite” he said.

Factional tensions between the conservatives and moderates are at boiling point and any early push on same-sex marriage could blow up party and possibly end Mr Turnbull’s leadership.

The issue came to a head on Monday when a speech by senior moderate Christopher Pyne to a closed function was recorded and leaked.

So bitter have the divisions become, that at a corresponding dinner of the party’s right wing on Saturday night, organised by the Young Liberal Movement and Eric Abetz’s office, conservatives who voted for Mr Turnbull in the 2015 leadership spill were excluded. These included ministers Alex Hawke, Michaelia Cash, Scott Ryan and Mitch Fifield. Mr Abbott received a standing ovation at the dinner.

“It’s who supported Abbott and who did not. That’s become the line in the sand,” said a senior source.

Gay marriage is now the flashpoint issue threatening to blow up the party.

Liberal moderates Dean Smith and Trent Zimmerman are reportedly behind moves to introduce a private members bill when Parliament resumes in August. It would only take a handful of Liberals to exercise their right to cross the floor to ensure the bill passed.

But the bill cannot be brought on for debate without the imprimatur of a government-controlled Bills Selection Committee.

To override this, some Liberals would also need to cross the floor to garner the minimum 76 votes needed to force the bill to be considered for debate.

This will be difficult. With Bob Katter opposed and Labor’s Kate Ellis away on maternity leave, the Liberals would need four floor crossers.

If they delay until September by when Warren Entsch goes to the United Nations for a three-month secondment, there will have to be five floor crossers.

Nonetheless, Mr Turnbull sent a stern warning to any moderates considering such a plan.

“People can raise what they like in the party room. Private members bills have to be considered by the Bills Selection Committee,” he told radio station 3AW.

“We do not support a bill relating to gay marriage being brought on until there was a vote of the Australian people.

“We will not support a vote in the Parliament until there has been a plebiscite. We are not going to change our policy.”

In comments made at the Black Hand dinner, a gathering of moderates held on the sidelines of every Liberal Party federal council meeting, Mr Pyne boasts the moderates are running the show and that same-sex marriage may soon be resolved.

“Friends, we are in the winner’s circle but we have to deliver a couple of things and one of those we’ve got to deliver before too long is marriage equality in this country,” Mr Pyne said.

Conservative Eric Abetz followed up from Tony Abbott on Tuesday in attacking Mr Pyne as treacherous for boasting about having always supported Mr Turnbull in leadership ballots. Senator Abetz indicated any push for same-sex marriage in the Parliament would be incendiary.

Mr Turnbull insisted “the party room is very harmonious, very united”.

“We have dealt with a number of difficult issues in recent times. Including education. Complex issues. Education, energy. We have come to very solid landings on that,” he said.

This article first appeared on AFR.com. See the original article here.

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