Mr David Trimble has cast doubt on this week's expected publication of British and Irish government proposals to break the political deadlock threatening the Belfast Agreement.
However, the Ulster Unionist leader appeared set on a potential collision course with London and Dublin yesterday, as he signalled that suspension followed by a major review of the agreement could lead to unionist attempts to renegotiate the terms of the accord.
Mr Trimble faced the prospect of increasing internal party opposition, as it emerged that Sinn Fein may have won its battle for fresh legislation taking the Patten reforms of the RUC beyond Mr Peter Mandelson's Police Act.
The UUP leader's toughened stance also coincided with speculation that the International Decommissioning Commission may be invited to produce an alternative to existing schemes set out in legislation for "putting weapons beyond use" which might not involve the actual "destruction" of weaponry.
On the BBC yesterday, Mr Trimble said failure to resolve the decommissioning issue would make it necessary to have the political process "untangled" from paramilitary organisations and their political representatives, and could see Sinn Fein expelled from ministerial office.
Amid speculation that the British Prime Minister and the Taoiseach had delayed last Friday's expected publication of their agreed plan in the hope of an IRA statement on arms, Mr Trimble told Breakfast with Frost: "If there isn't that clear action [on a start to decommissioning] over the next few days it may very well be that the proposals are held further back."
However, Mr Trimble appears alone in this expectation. Irish Government sources have confirmed their belief that Mr Blair's package of measures, agreed with Mr Ahern, will be published whether or not they get a positive IRA response.
One source said the IRA should respond positively "if only to show how flexible and generous the two governments have been" in their effort to break the impasse over decommissioning, demilitarisation, policing and the institutions of government.
Belief that the proposals will be published was further strengthened by reports yesterday that the Northern Ireland Secretary, Dr John Reid, has told the Police Authority that the measures for further policing reforms were "autonomous" and would proceed in any event.
The Irish Times understands that the lengthy and detailed document will make explicit the British government's readiness to enact further policing legislation. That would be consistent with a Sunday Times report yesterday that the proposed transformation of the RUC into the new Police Service may not be completed until next May.
However, if Sinn Fein has won the battle for fresh legislation, there are suggestions that the proposed recasting of the roles of the Policing Board, Ombudsman and Oversight Commissioner may not fundamentally alter the Northern Secretary's powers or the operational independence of the Chief Constable.
Despite the insistence from Mr Blair and Mr Ahern for speedy decisions by the parties, it is possible that a legal device allowing a one-day suspension and a new six-week deadline could throw the negotiations into September.