The British Prime Minister and the Taoiseach hope that strict security and a veil of secrecy will assist the two days of talks, which begin this morning, aimed at breaking the decommissioning deadlock and saving the Belfast Agreement.
There was relief in Dublin and London last night that, ahead of the crucial talks in Shropshire, England, the Drumcree parade passed off without serious incident yesterday.
Mr Blair and Mr Ahern will hold a bilateral summit meeting at Chequers this morning before travelling to the talks venue at Weston Park House, where they will join the pro-agreement parties for two days of make-or break discussions on the decommissioning-demilitarisation-policing impasse now casting a serious question mark over the survival of the Good Friday accord.
One week after his resignation as First Minister, the Ulster Unionist leader, Mr David Trimble, insists that the only question to be determined during the talks is whether the IRA is now ready to begin the decommissioning process.
Sinn Fein and the SDLP, on the other hand, are determined that the issues of demilitarisation, policing reform and the protection of the institutions of government against future political threat must all be resolved if a deal is to emerge.
Hopes that agreement might be forthcoming have been raised by the fresh devotion of prime ministerial time and the careful planning and relocation of the talks away from the gaze of the media.
Arrangements have been made to continue the talks into Wednesday if that proves necessary. However, London and Dublin insist that Mr Blair and Mr Ahern have no intention of allowing the talks to resume at the weekend in the aftermath of the Twelfth of July celebrations.
Senior unionist sources say privately that a "one-off gesture" by the IRA, possibly rendering unusable the weapons in the inspected dumps, would not be enough.
Despite the Taoiseach's declared preference for fresh Assembly elections, the expectation of the Ulster Unionist leadership is that a period of suspension will probably be necessary to permit a resumed negotiation in September.
In that context, attention has been given to a clause in the Belfast Agreement which some interpret as permitting a rolling series of six-week suspensions rather than the open-ended suspension imposed by the British government in February last year.
The British and Irish governments will be concerned at a hardline statement yesterday from the Sinn Fein president, Mr Gerry Adams, in which he appeared to rule out any imminent move on IRA weapons.
Addressing a hunger-strike commemoration in west Belfast, he said: "In my opinion there is no possibility of unionist demands on IRA weapons or British government demands on IRA weapons being conceded by the IRA in the time ahead. It is not possible, and it is not the responsibility of the Sinn Fein leadership to deliver the IRA on British government or unionist terms."