The DUP will this morning mount a legal challenge in the Belfast High Court to try to frustrate the scheduled election of Mr David Trimble and Mr Mark Durkan as First and Deputy First Ministers.
The DUP deputy leader, Mr Peter Robinson, and senior party officers met senior legal advisers over the weekend to plan how they might legally block or undermine Mr Trimble's attempt to be reinstated as First Minister today.
They are hoping the High Court will issue an injunction preventing the Assembly from proceeding with the elections of First and Deputy First Minister.
After the Alliance Party's weekend decision that at least three of its five members would temporarily switch designation to unionist Mr Trimble now should have the necessary number of votes to be restored in office today.
Mr Robinson believes, however, that the DUP can thwart this plan.
He refused to release full details of the challenge but he believed it could prevent Mr Trimble's election as leader.
He said last night that the Northern Secretary, Dr John Reid, had already admitted he failed to implement his statutory obligations to call elections when, from midnight on Saturday night, Northern Ireland was left without a First or Deputy First Minister.
"He can't act outside the law. He should either obey it or change it," Mr Robinson told The Irish Times last night.
The Northern Secretary, conscious of the potential legal challenge from the DUP, was extremely cautious when queried about the prospect of his being brought to book for failing to call elections after midnight on Saturday.
He acknowledged that he had a "statutory obligation" to propose an election date because as and from that time Northern Ireland did not have a First or Deputy First Minister.
However, he indicated that legally he believed it was "reasonable" not to immediately call elections as there was a strong prospect that the issue of filling these posts would be resolved today.
The Alliance party decided to re-designate at least three of its five MLAs following a frantic weekend of negotiations, which involved Alliance, Sinn FΘin, the SDLP, the Ulster Unionist Party, as well as Dr Reid, and by telephone contact with the British Prime Minister, Mr Tony Blair.
There was considerable internal party resistance to the move with former Alliance deputy leader and MLA Mr Seamus Close refusing to accept re-designation.
The Alliance leader, Mr David Ford, in an article in today's Irish Times said the decision was taken to safeguard the Belfast Agreement.
"The situation in which Alliance found itself this past weekend stank. But for those of us who want real stability and peace in Northern Ireland some of us are reluctantly prepared to hold our noses for a week," Mr Ford writes.
In return for temporarily adopting unionist designation Dr Reid, in consultation with the pro-agreement parties, is to initiate a review of the Assembly voting procedures, as is allowed under the terms of the agreement.
Rather than key decisions, such as electing First and Deputy First Ministers, requiring a majority of both unionist and nationalist MLAs Mr Ford favours a system whereby between 60 and 70 per cent of the overall Assembly would be sufficient.
The Taoiseach, Mr Ahern, at Bodenstown yesterday praised Alliance and the Women's Coalition for acting in the interests of the agreement.
A spokesman said the British Prime Minister lauded the re-designation decisions.
"He recognises it was a difficult and brave decision but they have put the interests of the people of Northern Ireland above their party positions," he said.
