Mr Jeffrey Donaldson today calls for the formation of a unionist coalition, including the Democratic Unionist Party, as the precursor to a renegotiation of the Belfast Agreement.
Launching his fiercest broadside yet against Mr David Trimble, the Lagan Valley MP insists the present Ulster Unionist leadership cannot represent majority unionist opinion in any negotiations on the future of Northern Ireland.
And, while insisting he has not yet made up his mind, Mr Donaldson gives the clearest signal that he is prepared to quit the party if Mr Trimble wins the crucial policy vote at Monday night's crunch meeting of the ruling Ulster Unionist Council (UUC).
In an interview with The Irish Times Mr Donaldson rejects suggestions that he is attempting to "blackmail" his party and refuses to go beyond his previous assertion that he would have to "consider his position" should the UUC fail to back his motion rejecting the British-Irish Joint Declaration as a basis for the restoration of the Stormont Assembly.
However, when asked if he might "have a Clare Short moment" and change his mind at the last moment, Mr Donaldson replies: "I've said I will consider my position and I've nothing to add to that because it would be a contradiction to say on the one hand you will consider your position after Monday but to have already made up your mind prior to Monday about what you are going to do. But let's be clear. I am not one who's given to rash pronouncements, when I say something I mean it. And if the Ulster Unionist Party gives its consent to proposals that give Dublin for the first time a say in the internal affairs of the Northern Ireland Assembly then that for me is a bridge too far."
Mr Donaldson says the Rev Ian Paisley's DUP has to be involved in any renewed political process and suggests the IRA will only finally deliver "closure on the conflict" in dealings "with a unionist bloc that is in a strong position and where they (the republicans) recognise they can no longer get away with simply exploiting the divisions and weaknesses of unionism."
Directly questioning Mr Trimble's authority, Mr Donaldson continues: "I do not think that we can go into negotiations again with only a minority of unionists represented at the negotiating table. That is not a viable proposition and the process is untenable in those circumstances."