The Ulster Unionist Party leader, Mr David Trimble, is this morning preparing to set in train a series of events which could decide the fate of his party.
When party officers meet this morning Mr Trimble is expected to urge them to convene a special meeting of the 860-strong Ulster Unionist Council, the party's governing body, to vote on the deal agreed in the recent Stormont talks.
The most likely date for the Ulster Unionist Council meeting is November 27th, although a later date is possible. A week's notice is required for the meeting, expected to be held at Belfast's Ulster Hall.
Plans have already been made for a major drive by the UUP leadership to win backing for the deal through the media and at grassroots level. Mr Trimble and his senior colleagues will lobby party constituency associations throughout Northern Ireland.
Opponents of the deal inside the party have been organising for some time against what they regard as a "sell-out". The dissidents will not be making a direct challenge to Mr Trimble's leadership but will argue against the package on offer.
Dissident sources estimate that each side in the debate has the support of about 40 per cent of delegates, with slightly fewer than 200 still undecided.
While senior unionists expect Mr Trimble to win the UUC vote, they say he must do so by a significant margin. Observers agree the vote in favour of the package will have to be at least 60 per cent to be convincing.
A professional marketing firm was hired by the dissidents to organise "focus groups" of two or three dozen unionists in different areas, to assess party feeling, and help devise the best way to defeat the attempt to form an executive without prior decommissioning.
Opponents of the deal have also been carrying out telephone canvassing among UUC delegates. "Attacking the leader is not going to win us friends," dissident sources said. They added they believed UUP members were anxious to avoid a split.
District councillors, who make up a significant proportion of UUC membership, are being urged by the dissidents to reject the deal because it will affect their chances of re-election in the May 2001 local government poll.
The dissident Ulster Unionist MP, Mr William Thompson, said last night he did not believe in the concept of power-sharing.
"I don't believe in power-sharing. I believe in British democracy and in Irish democracy, for that matter. I believe in proper democracy. Power-sharing means that there is no point in having elections," he said.
As Senator George Mitchell yesterday formally concluded his review of the Belfast Agreement, the president of the Northern Ireland Chamber of Commerce and Industry, Mr Owen Lamont, called on business leaders to support Mr Trimble.
He praised Mr Trimble as a man of "supreme political courage" and said a guaranteed peace would automatically produce prosperity. "We'll make the Celtic Tiger look like a pussycat in comparison," he said.
Yesterday President Clinton praised the political parties in Northern Ireland for having taken "a powerful step towards peace". Mr Clinton said he fully supported the Mitchell report conclusions and "we should all take heart from the fact that the parties have strongly reaffirmed their commitment to the Good Friday accord."
Last night, Senator Mitchell revealed that sharing meals had helped the success of the negotiations. The talks had been "very tough" until the venue moved to the US ambassador's residence in London, he said.
"We sat in the ambassador's living room. We shared meals together . . . I insisted that there not be any discussion of issues at the meals, that we just talk about other things so that they could come to view each other not as adversaries but as human beings and as people living in the same place and the same society and wanting the same thing."