PM's emergency gay marriage meeting

LIBERAL MPs have been summoned to a special party room meeting next Monday to bring the same-sex marriage debate to a head.

Government MPs were told this afternoon that the Liberals would meet in Canberra at 4pm, the day before Parliament returns after the winter break.

Significantly, it is set to be a Liberal-only meeting, after former prime minister Tony Abbott infuriated his colleagues in 2015 by bringing their National Party counterparts into the room when same-sex marriage was debated and the plebiscite policy was finalised.

Mr Turnbull said earlier today that any issue could be discussed by the Liberal party room.

"But, of course, ultimately Coalition policy is determined in the Coalition party room," he said.

Queensland MP Warren Entsch, a key marriage equality advocate in the government, argued Liberal MPs were "ambushed" when the Nationals were brought into the 2015 meeting.

"Instead of being ambushed and deceived, I trust this prime minister to do the right thing and give us an opportunity to have a fair hearing on this," Mr Entsch said earlier today.

Mr Entsch said the Nationals would be free to disagree with whatever the Liberals decided.

The decision to call a special party room meeting comes amid speculation that a secret ballot of MPs could be held to determine their preferred way forward on same-sex marriage.

The options would include keeping the plebiscite, moving to a postal plebiscite, and holding a free vote on the floor of Parliament.