The importance of arms decommissioning was stressed by the Taoiseach in the Dail before his London meetings on the North.

Mr Ahern said there was a consensus that the institutions needed to be restored as quickly as possible. "Everyone from republican and nationalist areas is calling on us to try to achieve that. We must remember there is also consensus that decommissioning is essential and that it will contribute to a wider demilitarisation.

"There is consensus on the fundamental principles of democracy as set out in George Mitchell's report, to which the parties signed up before they entered the multi-party talks. We cannot forget that the Mitchell review and the Mitchell principles are also part of where we are today.

"Everyone understands and accepts that participation in government can only be on the basis of a democratic mandate. Whether people like it or not, it is not compatible, beyond a short transitional period, to have that democratic mandate with armed backing. I could not agree to that.

"If the consensus is respected and acted upon it will provide the basis for reaching agreement with the other parties and it will enable the governments, acting together, to quickly put the implementation of the Good Friday agreement back on track. However, I cannot put only one part back on track; it must be all the parts."

The Fine Gael leader, Mr John Bruton, said he agreed wholeheartedly with the Taoiseach that not only was it a consensus of all parties in the House that the institutions be restored, and that decommissioning of weapons starts, but that the decommissioning of weapons had been democratically mandated by the people in their vote on the Belfast Agreement in all 32 counties of Ireland.

The Labour leader, Mr Ruairi Quinn, supported what the Taoiseach said. "The vast majority of people on both sides of the Border voted for the Good Friday agreement on the basis that Sinn Fein spoke for the entire republican movement. The mandate Sinn Fein received from the ballot box was on the understanding that it would in turn persuade the military wing of that movement to commence decommissioning in accordance with the overall terms of the Good Friday agreement.

"There is a breach of faith now. We must all work together to make it clear on this democratic island that unless someone has a mandate that enables him to speak authoritatively on behalf of the people who elected him, he does not have a role to play in Irish politics." Mr Austin Currie (FG, Dublin West) said: "These people have only contempt for us and for mandates."

The matter was first raised on the Order of Business by Mr Bruton, who asked the Taoiseach to join him in calling on the IRA to reinstate its contacts with the de Chastelain commission and to reinstate the proposal it made late last Friday, which had led to a positive report.

Mr Trevor Sargent (Green Party, Dublin North) said: "I appeal to the IRA to go back to the table with Gen de Chastelain and resume what was a promising, if a long drawn-out and painful process. While I wish the Taoiseach well in his meeting with the UK Prime Minister, Mr Tony Blair, I ask him not to forget the voices of people such as Monica McWilliams and David Ervine, who have appealed for inclusiveness to be maintained in the face of the temptation to polarise the situation.

"We must keep people on board and, if necessary, go back to the drawing board again, even if that means reviving the Forum for Peace and Reconciliation. The diverse voices, and the voices of reason which are often drowned out by the soundbites, should not be forgotten in the attempt to resolve this matter."

Mr Ahern said that on Tuesday night he had an opportunity to discuss in detail the events of recent days with the SDLP, whose ongoing efforts he appreciated. "Statements were made overnight about the inclusive process. Deputies Bruton, Quinn and Sargent are correct in what they said. It would be extremely useful in trying to take matters forward if we could get back to the position we were in last Friday.