Stage fright is probably the best description of the mood on the eve of the prime ministers' meeting. One can sense the nervousness. After their week in Weston Park, in the English midlands the Taoiseach is tomorrow morning due to join the British Prime Minister in his Sedgefield constituency in north-east England.
They were due to lift the curtain on their blueprint but such is the sensitivity around this whole initiative that late last night British and Irish sources said the presentation might have to be delayed.
Quite an amount of the expected proposals are already known. The most contentious deal with issues such as an amnesty for republican and loyalist paramilitaries on the run, former paramilitaries being al lowed to join the local policing boards and recruits to the Police Service of Northern Ireland not being trained in the use of plastic bullets.
The BBC reported yesterday that in line with Patten, the Union flag will not fly outside police stations and that the symbols of the force will be neutral. And as a quid quo pro for unionists, the Press Association reported that part of the package could include a review of the Parades Commission.
The two most difficult matters are policing and weapons. Demilitarisation and safeguarding the institutions, it seems, can be sorted, but policing will cause most pain for unionists.
Whether Mr David Trimble and perhaps equally as important, his potential successor, Mr Jeffrey Donaldson, and the rest of the UUP, can tolerate that pain will be largely down to whether there will be some gain on IRA arms. Indeed Mr Trimble's future as UUP leader probably depends on what the IRA will deliver.
One observer described the Weston Park talks as politicians trying to attach four wheels to a stranded car. Three wheels have been affixed, if not actually tightened, relating to policing, demilitarisation and safe guarding the institutions of the agreement, but the fourth wheel - arms - is so far missing.
As Mr Ahern and Mr Blair prepare to share the limelight in Sedgefield tomorrow morning, it is still uncertain what, if anything, the IRA will do on weapons. "But republicans must know that this car can't run on three wheels," the observer said. A senior Sinn Fein source insisted that the package must detail the amending legislation that the British government will introduce to bring the Police Act in line with Patten.
He released a document presented to the two governments on Tuesday reiterating the changes Sinn Fein is demanding in areas such as accountability, the Special Branch, flags and emblems, the oath, inquiries and several other matters.
Just as Ulster Unionists have been warning that the package faces outright rejection, there was an element of republican hard-balling here too. It would seem, however, that many of Sinn Fein's requirements could be met. But for unionists to suffer such police reform will require considerable reciprocation on arms.
The mantra from the British and Irish governments is that the document will be balanced, dealing with all four issues in a fair and workable manner.
Only a small coterie knows what the IRA will do. If it does not move, then there are great community dangers. The UDA has lost confidence in the Belfast Agreement and there is evidence that quite a number of the UVF are similarly minded. The sectarian violence and the pipebomb attacks are proof of that.
This is always a particularly worrying time for nationalists because in times of political turmoil, loyalist paramilitaries can strike out indiscriminately against them.
Within the broad unionist community there is also a steadily growing estrangement from the agreement - the election results are proof of that.
Republicans think strategically. They are aware of the future electoral gains to be made in the North and South if they act generously. But they are also conscious that irrespective of what they do, their strong core support will not desert them.
They are aware too of the alienated mood of loyalists and unionists and how far they should push it. They are also conscious of the blame game. If they do nothing, they, instead of unionists, will be censured. If they do just a little but not enough, then part of that blame will shift to Mr Trimble and the UUP. Equally, if they feel what is in the package generally meets their demands, they might do the unexpected and initiate a genuine process of putting IRA arms beyond use.
We can hardly expect to have definitive answers by tomorrow evening from the IRA, Sinn Fein, the UUP or anyone else, but in terms of mood we might have some sense of whether the UUP, the SDLP, the smaller pro-agreement parties, Sinn Fein, and by extension the IRA, can at least live with what is on offer.
The British and Irish governments are hoping for speedy responses when the document is presented but a more likely prospect is that we will hear holding statements with more conclusive replies later. This process could take us through the holidays into September.
What Mr Blair and Mr Ahern don't want to hear is clear and explicit "Nos" from either the UUP, Sinn Fein, the SDLP or anyone else in the Yes camp, and this could explain a last-minute warning that there could be a delay in presenting the blueprint.