The prime suspect for a bombing in Belturbet, Co Cavan, in December 1972 had been identified, Mr Caoimhghín Ó Caoláin (SF, Cavan-Monaghan) said.
He added that the second Barron report had made a significant statement on the bombing, which claimed the lives of two young people.
"Is the Taoiseach aware the report names a Fermanagh loyalist as the prime suspect and advises that in 1975, gardaí requested the RUC to question the named individual about the bombing?" Mr Ó Caoláin asked.
"Mr Justice Barron had to conclude in his report that he is not aware of the result, if any, of that request."
The Taoiseach, Mr Ahern, said Mr Justice Barron's comments on the 1972 and 1973 bombings in the Republic had been raised with the British Prime Minister, Mr Blair, some weeks ago.
"We also put our concerns in writing to the British on November 17th," he added.
"These matters are now in their system and I hope we will get some responses to that, but not at this stage."
The Green Party leader, Mr Trevor Sargent, asked if Mr Ahern intended to do anything about the apparent time-lag between February 2003, when Mr Justice Barron wrote to the Northern Secretary, Mr Paul Murphy, seeking information about the bombs, and the reply a year later which appeared to state that the British government had not yet been able to begin a further major and time-consuming search.
Mr Ahern said the matter of the lack of British co-operation with Mr Justice Barron's investigation had been raised with Mr Blair by way of letter. The matter had also been raised with the British government.
