Labour leader Eamon Gilmore has agreed to cross-party talks on multibillion-euro spending cuts but insisted that a general election was still needed.
In a distinctly cool response, Mr Gilmore said he would accept Taoiseach Brian Cowen's invitation to the opposition but stressed a four-year budget road map was not credible without a fresh government.
Mr Cowen bowed to a week of pressure and wrote to Fine Gael and Labour opening the door to a possible national consensus on the economy.
The Taoiseach stressed the letter reiterated his support for the plan - despite giving a lukewarm response to Environment Minister John Gormley's proposal in the Dail the previous day.
Mr Gilmore said he would not get involved in the talks to help relations between Mr Cowen and his coalition partner.
"I'm not going to engage in some kind of political marriage counselling between the Taoiseach and one of his ministers in the Government," Mr Gilmore said.
In his letter to Enda Kenny and Mr Gilmore, the Taoiseach said the pursuit of the national interest and common good must take priority. He said he wanted to confirm that all three parties were united in the belief that the economy must be put back on a sure footing by 2014, when the deficit has to be slashed to 3% of the value of the economy, or Gross Domestic Product.
Mr Gilmore said he would take part in the talks but added there was a need for a new government with a mandate to see through the four-year budgetary plan.
In his response to Mr Cowen's letter Mr Gilmore said the consensus plan was an attempt to keep Fianna Fail in power.
"While I am always willing to meet with you to discuss any matter of national importance, including the budget, I remain to be persuaded that this exercise is intended to do anything more than prolong the life of your Government," he wrote.