Australia's Opposition leader Tony Abbott has backed out of a deal with Labour and the Independents to 'pair' the speaker's vote.
The Coalition is also refusing to pair Government ministers travelling overseas during parliamentary sittings.
The ABC reports Labor is now looking at trying to lure a renegade Coalition MP to accept the speaker's job
An agreement by the two major parties and the independents in the aftermath of the federal election on 21 August, would have made sure the speaker's side of politics was not disadvantaged by donating a member to sit in the Speaker's chair.
It is now likely the Government will be forced to nominate a Labor speaker, which will reduce its majority from two to only one vote in the House of Representatives.
It means even a single absence from the Government's ranks could lead to defeat on the chamber floor.
The ABC reports Labor does have another option, but it is a long shot. It will try and lure a renegade Coalition MP to accept the speaker's job.
On Thursday Mr Abbott confirmed that he was walking away from the agreement, saying the deal was unconstitutional.
"I support parliamentary reform. I continue to adhere to every aspect of the agreement, except the pairing arrangement, which we now know is fundamentally unsound and just simply cannot proceed," he said.
Prime Minister Julia Gillard earlier attacked Mr Abbott for "breaking his word".