The Opposition will today challenge the Taoiseach, Mr Ahern, to deny in the Dáil that the Government did not have direct, or indirect, contacts with the "Real IRA" in the aftermath of the Omagh bombing in 1998.
Last weekend, the Sunday Business Post alleged Mr Ahern's former special adviser, Dr Martin Mansergh, organised secret ceasefire talks with the "Real IRA" through an intermediary, Father Alex Reid.
Questioned about the allegations yesterday, the Minister for Foreign Affairs, Mr Cowen, said: "I have made my position clear. The Taoiseach is making a full statement on Tuesday. That is the best place to leave it."
The newspaper said Father Reid had been in telephone contact with Dr Mansergh, who has since been elected to the Seanad, during a meeting with two alleged leading "Real IRA" figures, Mr Michael McKevitt and Mr Seamus McGrane.
Questioned about the allegations on Sunday, Mr Ahern dismissed them: "It is very easy to make a full comment: there was no contact. I understand that the newspaper is saying that the Government had contact after Omagh through Martin Mansergh.
"The Government had no contact whatsoever after Omagh, or at any other time," he declared, in response to a demand for a full explanation from the leader of Fine Gael, Mr Enda Kenny.
Mr Kenny returned to the offensive yesterday, although he said he accepted the Taoiseach's word there was no direct contact with the "Real IRA" after the Co Tyrone atrocity.
However, he asked Mr Ahern to confirm whether he had any knowledge of the meeting between alleged "Real IRA" figures and Father Reid in the Redemptorist Monastery in Dundalk, Co Louth.
"Can he absolutely deny that Father Reid undertook these talks at the behest of Mr Mansergh? Can he specifically deny that Father Reid in the course of the meeting in question was in contact with Mr Mansergh, who, in turn, is alleged to have been in contact with the Taoiseach?" the Fine Gael leader asked.
The Green Party leader, Mr Trevor Sargent, demanded "a full statement".
"If it emerges that the Government was more ready to negotiate with the terrorists than to consult with constitutional politicians that is a very dangerous message to send out at a time when a political vacuum has been created with the suspension of the Northern Ireland Assembly," Mr Sargent said.
Following a meeting with the SDLP leader, Mr Mark Durkan, in Iveagh House in Dublin yesterday afternoon, the Minister for Foreign Affairs, Mr Cowen, said he will meet the new Secretary of State for Northern Ireland, Mr Paul Murphy, on Wednesday.
He said he would take account of the concerns expressed by Mr Durkan and the SDLP's deputy leader, Ms Bríd Rodgers, who again urged that the parties be brought together quickly for a speedy "renewal, rather than review, of the agreement".