The Democratic Unionists are predicting they can block Mr David Trimble's re-election as First Minister in the Northern Ireland Executive in the crucial vote in the Stormont Assembly next week.
The DUP leader, the Rev Ian Paisley, last night confirmed the appointment of two DUP ministers - Mr Peter Robinson and Mr Nigel Dodds - following Mr Trimble's re-nomination of the three Ulster Unionist ministers on Wednesday in direct response to the IRA's decision to commence the disarmament process.
Mr Robinson again becomes Minister for Regional Development while Mr Dodds will serve as Minister for Social Development.
DUP sources said Mr Robinson and Mr Dodds would continue to act as "ministers in opposition" and justified the appointments on the grounds that failure to take-up their allocation of posts would see them re-distributed between other parties.
However Mr Robinson told The Irish Times there was no contradiction between this strategy and the party's determination to prevent Mr Trimble and the SDLP's incoming leader, Mr Mark Durkan, being elected as First and Deputy First Ministers when the Assembly meets for the purpose, almost certainly next Friday.
Mr Robinson confirmed the DUP's continuing purpose was "to force a re-negotiation" of the Belfast Agreement, and again said fresh Assembly elections should follow a failure to fill the top Executive posts.
He also expressed confidence that the dissident Ulster Unionist Assembly member Mr Peter Weir would "vote his conscience" against the restoration of the institutions of government on the basis of "a gesture" by the IRA. Mr Trimble is counting on fierce pressure from the Ulster Unionist Executive meeting tomorrow to bring Mr Weir into line behind his decision to resume ministerial office.
The UUP leadership clearly anticipates a softening in the attitude of some other "anti Agreement" unionist factions at Stormont as a result of the IRA decision, and some party sources appear confident Mr Trimble can secure re-election by a relatively comfortable margin. However on the basis of previously declared positions, Mr Weir's defection alone would be enough to divide the pro-Union camp evenly - 29 to 29 - and thus deny Mr Trimble the necessary majority of unionists voting.
In such circumstances attempts might be made to have members of the Alliance Party or Women's Coalition "re-designate" themselves as unionists for the purpose of securing the structures of government and Mr Trimble's return to office.
However existing Standing Orders - which might conceivably be changed by a vote of the Assembly - currently stipulate one month for such a re-designation process.
Some well-placed sources have also suggested that - following the procedural manoeuvres which previously allowed Mr Seamus Mallon's re-instatement as Deputy First Minister without a fresh vote - Mr Trimble might be allowed to withdraw his resignation of July 1st. Mr Robinson said last night that the DUP would fight any such move in the courts.
Mr Trimble's prospects received a boost yesterday when the leading dissident MP, Mr Jeffrey Donaldson, stopped short of opposing the party's re-entry into government with Sinn FΘin.
Speaking to the BBC's World at One programme from Australia, Mr Donaldson said the party should make its return "conditional" upon "the guarantee of further progress" in achieving "complete" paramilitary disarmament by next February, when the remit of the Independent International Commission on Decommissioning is scheduled to run out.
Commenting on clear indications that the British Government is prepared to extend the remit of the commission on decommissioning, Mr Donaldson said: "We've already extended this deadline twice . . . If we keep doing this we are going to fail to achieve our objective."
Arguing that the IRA, UVF, UDA and other paramilitaries remained "a potent threat", Mr Donaldson said: "If we are going to take the gun out of politics then we'll need to get on with the job."