The Minister for Transport, Mr Brennan, is to get limited legal representation at the Mahon Tribunal after Mr Gilmartin yesterday accused the Fianna Fáil TD of lying.
Proceedings began this morning with Mr Brennan's legal representative describing Mr Gilmartin's comments as "manifestly inaccurate [and] outrageous and untrue".
It was alleged that Mr Brennan lied in a statement to the tribunal when he claimed not to have met Mr Gilmartin at the meeting of Cabinet ministers in December 1989 in Leinster House.
Mr Rory MacCabe, for Mr Brennan, said that in light of the "false and arguably malicious accusation" his client had reversed his decision not to seek legal representation.
He said Mr Gilmartin and Mr Brennan both attended a meeting in September 1989 in connection with a separate matter. To his client's recollection that was the only time they had ever met, Mr McCabe said.
Judge Mahon said it was inappropriate to describe the testimony as malicious but rather a conflict of evidence.
He granted limited legal representation to Mr Brennan and said his solicitors would be entitled to cross-examine Mr Gilmartin in due course.
Mr Brennan later issued a statement through his solicitors saying there may have been a meeting about Mr Gilmartin's plans to develop Quarryvale at Leinster House. "[But] if there was, Mr Brennan was not there".