The Taoiseach and the British Prime Minister were this morning driving a dramatic bid to rescue the Belfast Agreement with a deal based on IRA acceptance of its "obligation" to decommission its weapons.
The Ulster Unionist Party leader, Mr David Trimble, would be required to agree the immediate triggering of the d'Hondt process and the creation of the Northern Ireland executive in "shadow" form.
Within one month of that, the IRA would be required, in a "voluntary" action, to put some weaponry "beyond use", in a manner acceptable to, and verifiable by, the International Commission on Decommissioning. Consequent upon that, the British government would complete the transfer of powers to the Northern Ireland Assembly and its executive.
Mr Ahern and Mr Blair returned to Hillsborough Castle for intensive negotiations last night, the Taoiseach having effectively overruled Mr Trimble's earlier, and seemingly "unilateral", adjournment of the talks process.
Mr Trimble returned to Hillsborough determined to negotiate substantial changes to the emerging British/Irish plan - understood to be rooted in ideas originated by Mr Seamus Mallon - amid warnings that the proposed agreement could split the Ulster Unionist Assembly Party and threaten Mr Trimble's leadership.
The plan, worked on throughout the day by Irish and British officials and set out on two pages, apparently does not contain provision for a specific, physical act of decommissioning or a timetable.
The Irish Times understands the key component of the plan would be an acceptance by the IRA that it is obliged to decommission its weapons under the terms of the agreement and to have completed that process by May 2000. This acceptance of obligation would be "copper-fastened" by both governments and augmented by an SDLP commitment to support Sinn Fein's exclusion should the agreement be broken.
Most of Mr Trimble's Assembly colleagues converged on Hills borough for a night-long negotiation, certain that Mr Blair had only returned in the belief that a deal could be struck, and knowing that it held the potential to make or break Mr Trimble's leadership.
There was speculation that Mr Trimble's deputy, Mr John Taylor, would lead those Assembly members determined that the executive should not be formed in either shadow or substantive form without a simultaneous act of IRA decommissioning.
While the immediate spotlight fell on Mr Trimble and the reaction of his party, Sinn Fein sources at Hillsborough continued to maintain their party line that the executive must be established without prior condition, and that the proposals under discussion had not been accepted and were not acceptable to them.
Shortly before 1 a.m. a spokesman for Mr Blair said the situation was "far better than we left it earlier today".
There were still the same outstanding issues and there were different ideas about how they might be resolved.
A Sinn Fein spokesman said that as far as his party was concerned there had been no movement or no progress and the situation was still deadlocked. He said Mr Blair's spokesman had a tendency to put a "gloss" on the situation.
The position of the Taoiseach and the SDLP was considered pivotal. They were expected to exercise leverage on Sinn Fein to agree a compromise, but republican sources cautioned that any deal involving short-term decommissioning was simply not acceptable.