Mr David Trimble appears locked in a race against time as leading dissidents press for an emergency meeting of the Ulster Unionist Council, possibly as early as next week, to determine the future of Northern Ireland's power-sharing Executive.
It is thought Mr Trimble had hoped to postpone the latest showdown with his opponents until at least early next month. However, there were reports last night that the 60 UUC delegates requesting the meeting - led by Mr Jeffrey Donaldson MP - have been supported by a legal opinion saying the meeting must take place in accordance with the party's rules within 21 days of receipt of the original requisition.
That requisition was handed to the party chairman, Lord Rogan, on October 4th, suggesting an outer deadline of October 25th, and a likely preferred date of Saturday week, October 21st.
After 90 minutes of talks in Downing Street last night, the Taoiseach, Mr Ahern, and the British Prime Minister, Mr Blair, set a "tentative" deadline of late next week for agreement on the range of issues threatening Mr Trimble's position as First Minister and continued UUP participation in the Executive.
One Whitehall source said there was "a recognition on both sides that time is short". The sense of urgency was underlined with confirmation that the disputed Police (Northern Ireland) Bill will not now go before the House of Lords until October 23rd at the earliest. The Bill is due to reach the statute book and become law before the new parliamentary session beginning in mid-November.
Irish officials said the convening of yesterday's summit meeting signalled the seriousness of the threat to the political process and the determination of both governments to overcome it.
Speaking after a lengthy one-to-one meeting with Mr Blair, the Taoiseach said they had agreed a programme of work to be carried forward by ministers and officials ahead of this weekend's planned meeting on the margins of the EU summit, and again in advance of the British-Irish Council in Dublin next Wednesday.
As the two leaders discussed their difficulties, the Northern Ireland Secretary, Mr Peter Mandelson, and the Minister for Foreign Affairs, Mr Cowen, reviewed the current state of the Police Bill.
Mr Ahern said he had conveyed the "strong concerns" of the Deputy First Minister, Mr Seamus Mallon, to Mr Blair, adding that there "are still difficulties in the legislation".
In a further attempt to reassure nationalists, Mr Mandelson told reporters the British Government would be bringing forward further amendments to the Bill in the Lords, and stressed that "the fundamentals" of the legislation implementing Patten would not be changed.
"The fundamentals of the Bill are in place. They are not going to change. We have now established a proper balance in the implementation of the Patten report," he said.
However, Mr Mandelson again said police reform would be conducted in a manner which did not "airbrush" the Royal Ulster Constabulary out of the history books or dishonour its record.
Contrary to the now-widespread impression, The Irish Times understands the Ulster Unionists are not actively seeking to reverse commitments already made by London on the implementation of the Patten proposals.
Sources in both capitals have confirmed that Mr Trimble's primary concern appears to be to preserve the amendment accepted by Mr Mandelson in July "incorporating" the name of the Royal Ulster Constabulary in the "title deeds" of the new Police Service of Northern Ireland.
And Mr Mandelson signalled the overriding importance of decommissioning yesterday when he again called on the IRA to honour commitments made in the May 5th negotiation at Hillsborough, which secured UUP agreement to re-enter the Executive on the basis of a republican commitment to open arms dumps to independent inspection leading to a process putting weapons "beyond use".
The Taoiseach acknowledged Mr Trimble's difficulties but said there were difficulties on all sides. "There are combined difficulties. What we have to do is find combined solutions," he said.