The Taoiseach has denied a member of Fianna Fáil met the IRA Army Council prior to the 1997 general election to seek a delay in implementing the group's ceasefire.
Mr Ahern was responding to a question in Dáil by Fine Gael leader Mr Enda Kenny who said the claim had concerned him for "a number of years".
The Provisional IRA called a ceasefire on July 20th, 1997, weeks after a Fianna Fáil/Progressive Democrats coalition was voted into power after a June 6th general election. The IRA had ended its 1994 ceasefire in February 1996.
Mr Kenny said: "I accept that you Taoiseach have put a great deal of effort and work into the business of attempting to bring forward and move forward the peace process. But there is something that has concerned me for a number of years and I like that you might clear it up here.
"It is a persistent claim out there that prior to the 1997 general election a member of the Fianna Fáil Oireachtas party met with members of the IRA Army Council and asked them to delay the implementation of their ceasefire.
"Now do you have any information or knowledge about that, and can you put this to rest for once and for all?" Mr Kenny asked.
Mr Ahern was "emphatic" that the meeting did not take place "in any form or in any way.
"I do not, in my knowledge, believe anyone in Fianna Fáil ever met the IRA Army Council and I don't think any such meeting ever took place with anybody asking that the ceasefire be delayed. I would be certain about that because I was deeply involved in that period."
Earlier, Mr Ahern said he had received intelligence briefings on the alleged activities of criminals with links to the Republican movement in Dublin port. "It is a Garda matter to be able to prove these matters conclusively . . . and that's a difficulty, an ongoing difficulty," the Taoiseach told the Dáil.
"I do think the Minister for Justice, in raising these matters, particularly in Dublin port, has indirectly seen a lot of action taken that may see an end to these criminality events," Mr Ahern said. "The activities of paramilitaries are affecting efforts to advance the peace process."
The Government intensified its attack on Sinn Féin's links with the Provisional IRA on Monday as both the Taoiseach and the Minister for Justice, Mr McDowell, claimed that the organisation was involved in "criminal heists" at Dublin port.
The claims were made ahead of a summit at Farmleigh tomorrow evening between Mr Ahern and the British prime minister, Mr Tony Blair. They are understood to refer to Garda intelligence about smuggling - involving cigarettes and video equipment in particular.