25/10/2015 1:46 PM AEDT | Updated 15/07/2016 12:50 PM AEST

Public To Vote On Gay Marriage 'Very Shortly After' Election

Ivonne Wierink via Getty Images
grooms wedding

A national vote on same-sex marriage will take place shortly after the next federal election, according to Assistant Treasurer Kelly O'Dwyer.

Prime Minister Malcolm Turnbull has been pushing for a public plebiscite to decide the controversial issue, while Labor wants the matter to be settled by a free vote in parliament.

Speaking to the ABC on Sunday, O'Dwyer backed a public vote, saying it would likely occur shortly after the next federal election.

"I think it's clear we will have a people's vote on this issue," she said.

"That was what was decided upon in the party room. We'll have a people's vote and it would be absolutely bizarre of a Parliament to ignore the will of the people.

"So once that people's vote happens, which I think will be very shortly after the election, I think the Parliament will respond."

She refused to be drawn on a more specific timeline for a public vote.

"It's up to the PM through discussions with the Cabinet to announce the timetable," O'Dwyer said.

The comments come after Federal Liberal backbencher Eric Abetz this week criticised colleague Warren Entsch for a proposal to decide the issue by a parliamentary vote.

Meanwhile, Turnbull said this week the exact mechanism of the plebiscite was yet to be determined, but that if it passed same-sex marriage would be made legal.

Independent Senator Nick Xenophon said on Sunday if the matter was going to a public vote, it should be settled fast.

"I support the Parliament dealing with marriage equality, but if the Government wants to have a plebiscite as they promised, then so be it. They should move on it quickly," Xenophon told reporters in Adelaide.

Nick Xenophon wants a vote on gay marriage to happen fast