THEY were trying to end the violence in Northern Ireland, but key players in the peace process sometimes came close to fighting among themselves. Bertie Ahern, the former taoiseach, has revealed that the invective hurled between Irish and British politicians during the peace talks was the worst he had ever heard.

“The level of abuse I heard grown adults give to each other has never been surpassed, and that includes in the back streets of Dublin or on football pitches,” he said in a BBC Radio Ulster interview to be broadcast on Friday. “There were no holds barred, I can tell you.”

Ahern believes one particularly vicious slanging match in 2001 had a therapeutic effect on the politicians because “the following morning they all got up and they all felt good because they had said what they thought”.

During the peace talks, his relationship with Gerry Adams, the Sinn Fein president, was particularly fraught, Ahern told David Dunseith, the presenter. This was partly because he refused to follow Sinn Fein’s advice on what the role of taoiseach should be.

“I had lots of rows with them, particularly with Gerry,” Ahern said. “I tried to take a balanced view because I was going to be no use to the process if I took a one-sided southern republican-nationalist viewpoint.” Despite these difficulties, he admired Adams and Martin McGuinness because “they have made hard decisions for militant republicans . . . and they have tried to move forward”.

He confirmed he had a tumultuous relationship with David Trimble, the then Ulster Unionist party leader. Jonathan Powell, a former adviser to Tony Blair, revealed in a recent book that on the morning of Good Friday in 1998, Trimble was “appallingly rude” to Ahern, who “came within an ace of hitting him, as he told us after the unionists had left the room”.

In the BBC interview Ahern says: “At some of the meetings with delegations he [Trimble] would let fly . . . I got a good insight into why he couldn’t do things.”

Asked if was indeed on the point of “chinning” Trimble, the former taoiseach said: “Maybe that is the way I looked. They reckoned in the room that I had taken so much abuse from him that maybe I looked as if I would, but I don’t think I ever was.”

Relations were far more cordial when Trimble and Ahern met privately. “When I was one-to-one with David I got on particularly well with him . . . You knew where you stood.” Ahern never took what was said in “the cut and thrust of tough negotiations . . . as a personal insult to me”.

Having previously ruled out standing for the presidency, Ahern now appears to be leaving the door open. He points out that it will not become an issue until early 2011, the year President Mary McAleese’s second term ends. He said he does not know at this stage if he will stand.

Ever since his retirement as taoiseach last May, Ahern has kept a high profile in public life, attending receptions, launching books and giving interviews. Many commentators speculate that the aim is to keep his profile high in preparation for a tilt at the Aras in just over two years’ time.

He agrees that speculation about his candidacy is inevitable. “You get people talking about what will happen, but my answer to that is very simple: it doesn’t come up for three years. [McAleese] is the president and I just don’t think it is even right people talking about who will be [her successor].”

Ahern played down suggestions he could have joined the IRA as a youth. “I don’t know if it ever came to that because our house was a Fianna Fail house,” he said. “But there were fellows I knew well growing up that did get involved in it. I watched them and I suppose they watched me.”

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