The Northern Secretary, Mr Peter Mandelson, is expected to suspend the two-month-old political institutions established under the Belfast Agreement this afternoon unless there is an unforeseen breakthrough in efforts to resolve the decommissioning crisis.
There is still hope in Government circles that IRA representatives will have a "meaningful engagement" with the head of the decommissioning body, Gen John de Chastelain, this morning. The hope is that they will say enough to the general to allow him to issue a further report or statement saying that he believes decommissioning will take place.
However, while Government figures still hoped last night for such a development, none appeared to expect it to happen. Yesterday for the first time the Taoiseach referred to the possibility of failure. Insisting he would "keep on trying till the last hour", Mr Ahern added that if there was no resolution, "we just have to keep at it and we will keep on working together".
The UUP leader and First Minister, Mr David Trimble, is understood to have told Mr Ahern unequivocally yesterday that either the institutions will have been suspended or he will have resigned by the time tomorrow's Ulster Unionist Council meeting is over. He insisted there was no other option in the absence of a breakthrough.
Government sources had indicated earlier yesterday that they were still seeking a formula which might avert both these options, even in the absence of a new IRA commitment on decommissioning, but the impossibility of this appeared to have been accepted by last night.
Mr Trimble later attempted to minimise any sense of impending disaster. He adopted an upbeat tone to tell reporters at Government Buildings that there was no "terminal crisis". "We do not want to see a crash taking place in the process. We will manage the difficulties and I am quite confident in our ability ourselves, the other parties in Northern Ireland, the Irish Government, the British government, that we have the capability of working through the difficulties," he said.
The Government yesterday still appeared to be seeking an alternative to suspension even in the absence of a breakthrough.
Mr Ahern told the Dail that "unilateral suspension" of the institutions established under the Belfast Agreement "would not be in line with the terms of the Good Friday agreement".
A Government spokesman last night acknowledged that the British government was legally entitled to suspend the internal Northern Ireland institutions unilaterally, although in practice such a move would normally happen after consultations between the governments.
Senior Government officials again spent the day in Belfast yesterday talking to Sinn Fein, Ulster Unionist, British government and SDLP representatives.
Mr Ahern was said to be in contact with these officials half-hourly throughout the day, and also spoke with the British Prime Minister, Mr Tony Blair, after his meeting with Mr Trimble. Irish officials also briefed White House officials on developments during the day.