Efforts to secure a deal between Sinn Féin and the Ulster Unionists to foster a positive atmosphere for elections ended last night in failure.
The Assembly poll will still go ahead on November 26th, but British and Irish sources conceded last night it appeared inevitable that devolution of powers to Stormont would not now go ahead as had been hoped before the debacle at Hillsborough last Tuesday.
An election to a suspended Assembly, followed by a new round of talks chaired by the Irish and British governments in December, is now the most likely outcome.
Electioneering has already begun, with sharp criticism of Sinn Féin by the SDLP, and bitter exchanges between the Ulster Unionists and the DUP.
Government officials returned to Dublin last night following efforts to encourage a deal.
Both governments believe the DUP and anti-agreement unionists within the UUP could make gains next month, making restoration of devolution even more difficult.
The UUP has cancelled tomorrow's scheduled Ulster Unionist Council meeting. It was originally hoped that the meeting of the party's ruling body would endorse a deal struck with republicans. Its cancellation marked the abandonment of pre-election efforts to secure agreement.
Mr Trimble left a meeting of the UUP officer board last night without making any public comment.
The chairman of the UUP executive council, Mr James Cooper, said: "We concluded that, regrettably, there has been no political progress upon which we should go ahead with that meeting.
"The party leader had made it clear that there would only be a meeting if there had been meaningful acts of completion by republicans which would enable us to proceed on a new agenda into this election.
"Through no fault of ours, that has not happened. We have concluded that there is no merit in that meeting."
The Taoiseach is expected to concede defeat later today in the efforts to reach a deal before the election.
Mr Ahern is expected to say that the outstanding issue concerning Mr Trimble's demand for more information about last week's act of IRA decommissioning cannot be resolved before the election campaign begins.
A source at Stormont told The Irish Times last night that the scale of any review of the Belfast Agreement would need to match the problems needing to be addressed. "The bigger the problem, the more fundamental it will be."