Northern Ireland's power-sharing institutions will be suspended on Monday, sources in the British government have confirmed tonight.
Earlier the Sinn Féin president Mr Gerry Adams warned the British Prime Minister Mr Tony Blair against suspension at what he described as "the whim of unionism".
But Mr Blair warned republicans in turn that they could no longer pursue a "dual strategy" of combining paramilitarism and politics.
The peace process has been in crisis since last Friday when the PSNI raided the Stormont offices of Sinn Fein amid claims republicans were involved in intelligence gathering. Sinn Fein says the raid was politically motivated to put the blame the party for the collapse of power-sharing, rather than on the Ulster Unionist Party which had planned to walk out next January.
The British government was expected to move next Monday to suspend the Stormont Assembly and power sharing institutions in an attempt to save the Belfast Agreement.
Sources expected two additional ministers to be appointed from Westminster to serve under Dr Reid, bringing the total number of junior ministers in Belfast to four.
Between them, they would assume responsibility for the running of the 10 Stormont government departments - covering everything for health to transportation, agriculture to education, the environment to the arts.
Dublin and some Northern Ireland parties have been ambivalent about the idea of suspension - accepting the need to protect the Agreement but uncertain whether the tactic could produce a deal which would quickly resurrect the power sharing arrangements.
As Sinn Fein prepared for rallies tonight in Belfast and Dublin to inform its activists of the party's strategy in the months ahead, Mr Adams warned that suspension could create a dangerous political vacuum.
Emerging from Downing Street with a delegation which included Sinn Fein ministers Mr Martin McGuinness and Ms Bairbre de Brún, Mr Adams said they had warned Mr Blair "against a long vacuum which will be filled by those who want to tear this down.
"To suspend the institutions once again would be a mistake," he said.
"It would characterise the institutions as optional extras, as being something that is given or taken away again depending on the ability of unionism to live with what is happening."
He insisted that republicans remained committed to the Belfast Agreement. "We are wedded to this process. We will continue to do our best to move this process on to make progress possible," he said.
Talks have been arranged between the Taoiseach Mr Ahern and the Ulster Unionist Party leader Mr David Trimble tomorrow ahead of a meeting of the Northern Ireland First Minister's party executive.
Mr Trimble has also argued against suspension, urging Mr Blair to instead lay a motion before the Northern Ireland Assembly to expel Sinn Fein from the power sharing executive over the spying allegations.
Ulster Unionist minister Michael McGimpsey criticised plans to suspend the Assembly, saying it was "wrong to punish the innocent with the guilty".
Mr Ahern tonight said he was strongly opposed to delaying a May election. He said he did not think an exclusion motion in the Assembly would be helpful, and that it would create its own difficulties.
Speaking in Dublin, he said: "Whatever happens to any part of the institutions in the short term, what we are most concerned about is how we can repair that in the medium term and get it up and running and functioning again on the other side of an election that is legally down to happen on May 1st.
"So we have to do all we can to make sure that whatever short term damage and whatever short term difficulties can be corrected over the medium term.
"I would be totally opposed to delaying the election. The election is fixed, it is a democracy, the people have their say and I do not see circumstances that should delay the election."
He said that if there was a suspension, it was important to look at the mechanisms that should be put in place to manage and keep functioning the Agreement.
The SDLP leader Mr Mark Durkan tonight said suspension of the political institutions in the North would only injure the Belfast Agreement and not kill it.
The Stormont Deputy First Minister said his party was opposed to suspension but did not believe in recrimination. "As a forward thinking party, our minds are on the big question: how do we get out of this mess?" Mr Durkan said.
Additional reporting PA