Junior coalition partners the Greens are to decide whether to pull out of the Government over the dramatic resignation of Taoiseach Brian Cowen as leader of the ruling Fianna Fail party.
TDs and senators are holding crisis talks to discuss the future of the troubled coalition.
Mr Cowen has bowed to an onslaught of pressure and criticism from former allies and quit as party leader after an epic week of political chaos sparked by a failed leadership heave, six ministerial resignations and a botched Cabinet reshuffle.
However, the Taoiseach vowed to stay on as head of the coalition government until the March 11 General Election.
The Greens threatened to bring down the Government on Thursday in the row over filling Cabinet seats left empty by the string of ministerial resignations but remained in the coalition to ensure the passing of the Finance Bill, which gives effect to Budget 2011 and other new cost-saving measures.
But the main opposition parties have now agreed to facilitate the passage of the proposed legislation by the end of the week in return for the election date being brought forward.
Fine Gael has also threatened to table a motion of no confidence in Mr Cowen as Taoiseach in the Dail next Tuesday, as a motion of no confidence in the Government is being debated, unless an immediate date for the general election is set.
Meanwhile four senior Fianna Fail politicians have begun to canvas for support in the leadership race.
Former foreign affairs minister Micheal Martin, who last week failed to get the support from party colleagues for a heave, is now a front runner.
Finance minister Brian Lenihan, tourism minister Mary Hanafin and social protection minister Eamon O Cuiv also intend to fight it out for the post - to be filled on Wednesday.