The Taoiseach Mr Ahern is reported to have joined the pay talks at Government Buildings when they resumed at 7pm.
Along with the Tanaiste Mary Harney and the Minister for Enterprise, Trade and Employment Michael Martin, Mr Ahern is also reported to have met union representatives this evening to talk about the problems still facing the talks.
Turlough O'Sullivan, IBEC Director General, earlier today indicated that employers were prepared to show some flexibility on wage rises.
Department of the Taoiseach secretary general Dermot McCarthy has been in contact with Ibec and Ictu leaders yesterday in an attempt to find some common ground.
Yesterday both sides were later called to Government Buildings for separate discussions with Mr McCarthy, but there were no direct negotiations.
A wide gap remains between the two sides over key issues such as basic pay increases and the duration of any new deal.
Tonight will provide the last chance for the sides to agree a deal before the Taoiseach departs for New York for a speaking engagement at the United Nations.
He is scheduled to address a UN conference on aid and leaves Dublin tomorrow morning. He has also said there will be no talks over the June bank holiday weekend.
Mr Ahern warned yesterday that time was running out. "There comes a time, and I think we're very close to it, when people have to decide whether they want to do a deal or not," he said.