The IRA is expected to issue a statement within 48 hours saying it will put its weapons "completely and verifiably beyond use", in a dramatic move that could bring about restoration of the North's political institutions on May 22nd.
A startling breakthrough at the end of a day of intensive talks at Hillsborough brought a British government commitment to restore the Assembly and Executive by May 22nd, the second anniversary of the approval of the Belfast Agreement. Such a restoration would be conditional on a positive response from all parties and in particular, from paramilitaries.
The outline of the new IRA statement on decommissioning is understood to have been put to the Ulster Unionist Party last night. After the apparent deal was announced the UUP had no response except to say that it hoped the republican movement "will tell us what they are going to do".
If the deal is to result in the restoration of the institutions, the IRA will this weekend move beyond its conditional commitment to decommissioning given to Gen John de Chastelain of the international decommissioning body last February.
If the IRA statement is as envisaged, the UUP leader Mr Trimble will then try to sell to his party a deal without IRA "guns up front", but based on a strong commitment to arms being "completely and verifiably" put beyond use.
The British and Irish governments will today present the party leaders with a joint letter setting out how and when the various outstanding elements of the Belfast Agreement would be implemented. This is expected to cover such key issues as police reform, human rights issues, criminal justice and a scaling down of the British army presence in Northern Ireland.
The latter issue of demilitarisation is contingent on the IRA and loyalist paramilitaries agreeing to put their arms "beyond use". No date for this is included in the joint government statements.
Today's letter will also deal with the issue of police reform, on which Mr Trimble and his party spent much of yesterday seeking some concession to appease unionist anger over plans to dilute the Britishness of the RUC's badge and symbols, and to change the force's name.
The Taoiseach said last night he believed the deal "will provide the basis to get the institutions up and running . . . I would be very disappointed if the response of the paramilitaries is not extremely positive," he said.
The British Prime Minister said it was now incumbent on the political parties "and, in particular, paramilitary organisations to give their response to the proposals we have made. I hope that response is positive."
Sinn Fein and the Ulster Unionist Party last night had their most serious engagement since the suspension of the institutions almost three months ago. It was this engagement, sources say, that allowed both parties to trust each other enough to run with this deal.
Yesterday's talks were the culmination of the most intensive effort yet to restore the power sharing Executive, Assembly and North/South bodies suspended on February 11th last.
A nationalist source said the outline of a deal was clear, but that if it were to be agreed the parties would have to accept "pain all round".