Former minister Ray Burke says he has no memory whatsoever of property developer Tom Gilmartin attending a meeting of ministers in Leinster House.
But Mr Burke says he would have had no difficulty with such a meeting as Mr Gilmartin was trying to bring in investment at the time.
Mr Burke told the Mahon Tribunal that his diary suggests he was at other meetings when Mr Gilmartin claims he met ministers in early February 1989.
He said that the Taoiseach, Bertie Ahern, was right when he said delegations were often introduced to cabinet members in the ministerial corridor situated in Government buildings.
But he pointed out that Mr Gilmartin had said the meeting took place in another part of Leinster House.
Earlier, Mr Gilmartin told the tribunal that he informed the Taoiseach about a demand for £5 million which he says was made in Leinster House.
Mr Gilmartin said that during a telephone conversation in 1989, he also told Mr Ahern about other demands for money.
The developer claimed that Mr Ahern, who was then Minister for Labour, put him in touch with Councillor Joe Burke and relayed his difficulties to him.
Under cross-examination this morning, Mr Gilmartin also said he made a £50,000 donation in June 1989 to then minister, Pádraig Flynn, out of desperation.