Christopher Pyne has confirmed Parliament will continue sitting beyond December 7 to legislate same sex marriage before Christmas.
The Leader of the House and Minister for Defence Industry said the senate has set a timeline that means it is unlikely to finish debating the marriage equality bill until November 30.
"The House will resume on December 4 at 10am, not November 27, and will sit until marriage equality is law and all citizenship issues have been dealt with by the house," he said.
"While it is entirely possible both matters could be dealt with in the week beginning 4 December, Members should be prepared for the House to sit for some or all of the second week beginning 11 December or as long as it takes (to) legislate for marriage equality and resolve all citizenship issues."
The announcement follows Flynn MP Ken O'Dowd and his colleagues being told to put plans "on hold" between December 11 and 15.
MID-DECEMBER plans are on hold as Member for Flynn Ken O'Dowd and his colleagues expect a potential two-week extension of the final parliamentary sitting this year.
Mr O'Dowd has been told to "put any plans on hold" between December 11 to 15, an indication Prime Minister Malcolm Turnbull could force parliament to run longer than the scheduled final sitting day of December 7.
The Liberal Party member said it was likely it would be the same-sex marriage legislation that could force the prolonged visit to Canberra.
But he said given the recent "uncertain times" and "sudden changes" he could not be sure.
Mr Turnbull's goal is to legislate same-sex marriage before Christmas, but he has not confirmed if he would extend parliament to do so.
"It's very uncertain times, there's changes happening on a daily basis," Mr O'Dowd said.
"My diary is full, it's already filling up for next year, so it does make it a little bit awkward."
Meanwhile, another controversy could impede the already wounded government, with a rebel Nationals member threatening to go rogue and cause "political damage".
In a letter to the Prime Minister, George Christensen has warned he will vote against the Liberal National Party after December 4 to get a commission of inquiry into the banking sector and restore penalty rates.
"My position about crossing the floor on both of these matters is final, and no amount of lobbying or proposal of other policies ... will alter my position," Mr Christensen wrote.
The threat comes as Mr Turnbull's leadership is hanging by a thread, currently holding 74 of the 150 seats.
The future of his minority government will be decided after the by-elections for victims of the citizenship debacle, Nationals' Barnaby Joyce on December 2 and Liberals' John Alexander on December 16.
Despite Mr O'Dowd not having read Mr Christensen's letter at the time, he said the Dawson MP needed to learn how to "fight within the tent".
Not surprised by Mr Christensen's latest threat, Mr O'Dowd, who once described the actions of Australia's banks as "blatant abuse of power", said he was unlikely to support his colleague's recommendation for a royal commission.
"He's entitled to cross the floor ... that's democracy at work," Mr O'Dowd said.
"A royal commission looks into what has happened in the past ... all it will find is what we already know.
"There's been mischievous work by banks when it comes to lending money.
"We should have a policy looking at the future that would prevent this from happening again."
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