Sinn Fein and the Ulster Unionists are believed to be very close to a deal which could see the creation of Northern Ireland's power-sharing executive by early next month.
Sources say the quality of a republican commitment to the International Decommissioning Commission, headed by Gen. John de Chastelain, will be the key issue in determining the success or failure of the Mitchell review, now entering its tenth week.
Senator George Mitchell will resume his talks with the parties at Castle Buildings, Stormont, this afternoon, amid mounting speculation that he could table a definitive plan for breaking the devolution/decommissioning impasse as early as tomorrow or Wednesday.
While nothing is yet certain, it is believed Sinn Fein and the Ulster Unionists have agreed the general structure of a sequencing process which, over a period of weeks, would lead to the triggering of the d'Hondt procedure for the appointment of ministers. Internal party talks, as well as discussions between some senior negotiators, continued at the weekend.
Arrangements are in hand to ensure that setting up the other institutions prescribed by the accord - the North-South ministerial council and the British-Irish council - would quickly follow the creation of the executive.
However, all such planning now seems to turn on Gen. de Chastelain's assessment this week, and whether he can secure a republican commitment on decommissioning specific enough to persuade Mr David Trimble to agree to the prior formation of the executive.
In his assessment last July the general said he believed that "to retain confidence in the process, actual decommissioning would have to begin within a few weeks of the start of the decommissioning process". In the scenario envisaged then, the process of decommissioning would have started with the appointment of paramilitary interlocutors to deal with the international commission, which it was anticipated could have occurred "literally a couple of days after devolution."
Yesterday's Sunday Tribune reported that IRA leaders have been briefing their members to expect a Northern deal in the next fortnight - coupled with a republican commitment to engage in "tactical" decommissioning. The report suggested the use of the adjective "tactical" might be intended to reassure IRA members this would not be an irrevocable step but rather one "dependent on the unionists keeping their side of a deal" which would put Sinn Fein into the executive.
Mr Trimble's ability to bring his party with him is cited as the second key factor in determining ultimate success or failure. The growing belief is that Mr Trimble would seek to pre-empt his anti-agreement opponents by calling a special meeting of the ruling Ulster Unionist Council to endorse any deal reached.
Mr Trimble's internal opposition also impinges on another outstanding issue - the problem caused by Mr Seamus Mallon's resignation as deputy first minister last July.
Under the existing rules, Mr Mallon's resignation requires a complete re-election of both the first and deputy first ministers, on a joint ticket, and by an absolute majority of designated "unionist" and "nationalist" members of the Assembly. The pro- and anti-agreement forces in the Assembly are evenly divided, 29/29, which means that - unless some members of smaller parties agreed to re-designate themselves as unionists - Mr Trimble might be unable to secure his re-election or Mr Mallon's return.
British officials are understood to have examined possible rule changes to reduce the electoral threshold or remove the need for a complete re-election, but such changes might be open to legal challenge.