The Taoiseach, Mr Ahern, has made the most forceful Government attack on Sinn Féin since the peace process began, directly linking the party's five TDs to violent actions which, he said, were being turned on and off for political reasons.
In the most bitter Dáil exchanges ever heard between a Fianna Fáil leader and Sinn Féin, Mr Ahern yesterday detailed recent, brutal, so-called punishment attacks in Northern Ireland, which he said had been carried out by the IRA.
He said he found it "really offensive" that these attacks were stopped during the political talks before Christmas, only to be resumed as soon as those talks failed.
The Dáil confrontation follows a robust meeting between the Government and Sinn Féin on Tuesday at which the Taoiseach demanded that Sinn Féin now come up with a solution to the deadlock over the continuation of IRA criminal activity.
Yesterday's proceedings demonstrated the major deterioration in the relationship between the Government and Sinn Féin after several years of closeness during the slow evolution of the North's political process. This deterioration has followed the Northern Bank raid in Belfast in December, which the Irish and British Governments, the PSNI and the Garda Síochána say the IRA carried out.
Speaking largely without notes and in a tone of controlled anger, the Taoiseach said what had annoyed him most was the apparent control that could be exercised over the IRA during political talks.
"What I find really offensive . . . is that there was an ability to turn off all punishment beatings while negotiations were in progress, but as soon as the negotiations failed there was a string of them - they are again a nightly occurrence. I will give Sinn Féin full marks for discipline, but not for anything else."
The Taoiseach's vehemence was matched by Sinn Féin TD Mr Caoimhghín Ó Caoláin, who accused the Taoiseach of making his "continual outbursts and allegations" solely because Sinn Féin is an electoral threat to Fianna Fáil.
Mr Ahern said if his motivation had been to prevent Sinn Féin's electoral progress, he would not have worked so hard to bring them to the centre of politics in Ireland.
He said Sinn Féin used to be a party with 2 per cent support, but the tolerance and encouragement extended to them by his party and other parties in the House had allowed them to develop a significant electoral mandate.
The Minister for Defence, Mr O'Dea, accused Sinn Féin of funding election campaigns with stolen money.
And speaking directly to Mr Ó Caoláin, the Taoiseach said: "you and some of your friends" had carried out a series of brutal attacks in Northern Ireland in recent days.
The Sinn Féin TDs sat stony- faced as Mr Ahern listed some of these attacks to a silent chamber. "An 18-year-old received gunshot wounds in both hands in an incident in Seaford Street in east Belfast, responsibility of the Provisional IRA. "A punishment attack was carried out on a 19-year-old man. He was shot in both hands and it is believed the Provisional IRA was responsible. The other day a 19-year-old man was shot in both ankles in an alley in Serbia Street, Lower Falls and it is believed the Provisional IRA was responsible."
When Mr Ó Caolain challenged him to provide evidence, he said: "Does the Deputy want me to name the individual? What would happen to him?"
Mr Ó Caoláin said the Taoiseach was "abusing his position without evidence".
Mr Ahern said: "I will defend the facts."
He said progress now depended on how Sinn Féin responded to the Government's questions on the issues of criminality and decommissioning and "that does not rest with me. "It is an issue which rests with the Sinn Féin leadership and the opposite side of the coin, the Provisional IRA."