The Taoiseach has conceded for the first time that he may have been among a group of ministers who met the developer Mr Tom Gilmartin in Leinster House in early 1989.
His evidence gives increased credibility to Mr Gilmartin's insistence that he met seven ministers in February 1989 in relation to his plans for two massive shopping developments in Dublin.
Mr Ahern faced robust cross-examination yesterday during an unprecedented five-hour appearance by a Taoiseach before a tribunal of inquiry and a crowded public gallery. Afterwards, he told journalists he was glad his "long wait" to give evidence was now over.
The Taoiseach agreed that a "chit-chat meeting" could have taken place between some ministers and Mr Gilmartin, although he had no specific recollection of it.
However, he repeatedly rejected the characterization of any such encounter as a "meeting" in the formal sense.
This is a modification of his written statement to the tribunal some months ago that "it is my firm belief that I did not attend such a meeting".
Mr Ahern yesterday explained this written statement by saying he was responding to a request from the tribunal for any recollection he had of "a meeting with members of the Cabinet to discuss his plans for Quarryvale". He would count such an encounter as a formal meeting, and he believed none had taken place.
But, he went on, "if you asked me the question that we are now not talking about a meeting at all, that there could have been a casual chitchat with a few ministers . . .That of course could have happened."
Mr Ahern's evidence yesterday means that his account is not now in conflict with that of former minister Ms Mary O'Rourke, who told the tribunal last Monday that she was at a meeting broadly similar to that described by Mr Gilmartin. The then minister for industry and commerce Mr Albert Reynolds has moved from saying he did not attend such a meeting to saying that he does not recall such a meeting.
Mr Ahern also appeared to accept now that Mr Gilmartin had spoken to him by phone about his plans for Quarryvale. Previously, the Taoiseach had told the Dáil his only contact with Mr Gilmartin concerned a separate plan to develop a shopping centre at Bachelor's Walk.
He said he had no recollection of the phone-call with Mr Gilmartin but accepted, having read the evidence of others, that he had referred the developer's inquiry about the purchase of land in Quarryvale to a friend, Cllr Joe Burke.
Mr Ahern agreed with lawyers for Mr Gilmartin that the developer was not "shifty" and had not given "dishonest" evidence, as his own legal counsel had claimed. However, he declined to dissociate himself formally from this description of Mr Gilmartin by his counsel, Mr Conor Maguire SC. He also said Mr Gilmartin had changed his story several times and had given an inaccurate description of the room in which the meeting is alleged to have taken place.
The Taoiseach now accepts he had three meetings with Mr Gilmartin in 1988 and 1989, as well as one phone call. Mr Gilmartin says they first met in 1987 and that they had four meetings and two phone calls as well as the meeting involving other ministers in Leinster House.
The tribunal is due to hear from other ministers who are alleged to have attended the meeting in Leinster House after Easter. Mr Gilmartin has claimed that he was accosted by an unknown man immediately after the meeting and told to deposit £5 million in an Isle of Man bank account. After completing his evidence, the Taoiseach told reporters he enjoyed putting his story and that he had answered all the questions put to him. He had earlier thanked the tribunal for fixing his appearance for yesterday so that he would be free for EU presidency work after Easter.
Asked had he found the questioning tough he said: "No, I have to say I've been waiting since January 1999 to get this opportunity. I said in the Dáil on the 27th of January, 1999, that I would go to the tribunal, that I would fully comply with the tribunal and I would put up with whatever cross-examination that was required.
"I've done that for five hours and 25 minutes, that's the way it should be and needless to say I enjoyed putting my story because it was a long time to wait to do that."