The Taoiseach has appointed a senior civil servant from his Department to chair an inter-departmental committee dealing with the families of the victims of the Monaghan and Dublin bombings. The attacks killed 33 people and hurt more than 120.
Mr Wally Kirwan, assistant secretary at Mr Ahern's Department, will head the committee drawn from the Departments of Justice and Foreign Affairs, to examine existing and new evidence related to the 1974 bombings and to establish if there are enough issues to proceed to an inquiry.
The Government is focusing on the affidavit of a former RUC Special Branch officer, Mr John Weir, which states the bombs used in the attacks were made from explosives provided by an officer of the Ulster Defence Regiment, since incorporated into the Royal Irish Regiment.
He also claims the devices were assembled in a house owned by an RUC officer and the attacks were carried out by a group involving a UDR man. His evidence also states British army intelligence and the RUC were aware of the identities of the bombers but that they were not questioned.
It is understood Mr Ahern was referring to Mr Weir's testimony in the Dail yesterday when he referred to "two substantive cases which are not on the records" of either the Department of Justice or the Garda. The other case he referred to is believed to involve the evidence of a retired member of the British security forces.
The evidence of both of these individuals is now being examined by the gardai.
Mr Ahern said: "Submissions have been made by more than one person on this matter. I will not identify those who have given information but I will not ignore that information. I cannot say if the information is factual but there are two substantive cases which are not on the records."