Efforts to save the devolution settlement at the heart of the Belfast Agreement will reach a critical stage this afternoon when Taoiseach Bertie Ahern meets British prime minister Tony Blair in Downing Street.
Mr Blair and Mr Ahern will endeavour to agree a date for the resumption of the suspended Stormont Assembly and a realistic timeframe for the restoration of an inclusive power-sharing executive.
Official sources said last night that the absence of pre-talks "spin" underlined the importance of today's meeting between the prime minister and Taoiseach, who led the Northern Ireland parties - minus the DUP - to the historic agreement almost eight years ago.
And Downing Street continued to resist suggestions that Mr Blair and Mr Ahern might be at odds over the latest British initiative to restore the Assembly with initially limited powers coupled with an absolute deadline for an Assembly decision on the appointment of an executive.
While no breakthrough announcement will be made today, the prime minister's official spokesman insisted that Mr Blair's thinking about the way forward "continues to clarify".
No 10's hope is for "momentum" this afternoon, pointing to an immediate programme of work for officials on both the content and date of an announcement.
Irish officials have been likewise reluctant to second-guess the Taoiseach's position, despite a deliberate lowering of earlier expectations and the description of this afternoon's meeting as a "stocktaking" exercise.
Senior sources in both capitals accept that the past experience and shared determination of the Taoiseach and prime minister will be key to any effort now to break the political impasse.
However, the challenge facing both men was underlined again last night when Sinn Féin president Gerry Adams insisted that any timetable agreed by Mr Blair and Mr Ahern should have the Rev Ian Paisley's DUP in a power-sharing government "before the summer and well in advance of the loyalist marching season".
In the absence of agreement within that timeframe, Mr Adams said, the Assembly should be scrapped and that London and Dublin should then proceed by way of "intergovernmentalism" with the equality agenda and the implementation of all other aspects of the agreement for which they have direct responsibility. The SDLP is equally vigorously opposed to the return of the Assembly in any sort of "shadow" form.
Ulster Unionist leader Sir Reg Empey has called for "a floor" and "a date" to be set for the conclusion of any new initiative, accepting that it may not be possible to salvage the devolved institutions.
His predecessor, former first minister David Trimble, has said Mr Blair should set the date for the resumption of the Assembly with its statutory six-week limit to nominate an executive, but with no fresh elections in the event of failure.
Sinn Féin has set its face against any form of shadow Northern Assembly leading to a fully functioning Assembly because it does not trust the British and Irish governments to honour such a commitment to the full restoration of devolution, according to Mr Adams.
He made it clear yesterday that one of Sinn Féin's chief reasons for not testing the proposal was his suspicion about the bona fides of the governments.
"Quite frankly, who would believe the governments, if they say they would do whatever sources say they might do in six months' time?" he said.
Mr Adams said the British and Irish governments should now set a deadline for restoring the Assembly and executive before the summer. And if the DUP did not sign up to such a plan then the governments should proceed with implementing other elements of the agreement.
SDLP leader Mark Durkan said Sinn Féin must acknowledge that there were serious flaws in the aborted comprehensive agreement, which the British and Irish governments negotiated with Sinn Féin in late 2004.
Mr Durkan, in a damning critique of this blueprint, which came unstuck in early December 2004, said Sinn Féin, the governments and other parties must reject the document because it undermined the agreement.