Sinn Féin is considering a legal challenge to the Government's decision not to put the EU/IMF bailout deal to a Dáil vote.
The party said that the Government is acting unconstitutionally in its failure to allow TDs to have their say on the deal.
Sinn Féin President Gerry Adams said: "Any new government should refuse to honour the terms of the IMF/EU deal and Sinn Féin will seek a mandate in the General Election to renegotiate it.
"This Government has no mandate to impose the terrible deal it has negotiated with the IMF and EU.
"The interest payments alone will cripple our public finances for years.
"The people of Donegal South West have clearly endorsed Sinn Féin’s proposals for a better, fairer way forward. They have signalled that the Government must go."
Sinn Fein has also announced plans to enter talks with two independents to form a technical group which would give the party more speaking time in the Dáil.
Its newest TD Pearse Doherty takes his seat in the house today pledging to oppose the budget and the IMF rescue loan.