Mr Tony Blair will today make a strong attempt to boost the unionist Yes campaign in the North and to win dissident Ulster Unionist MP Mr Jeffrey Donaldson's backing for it.
Rising British and Irish government concern about the current state of unionist opinion on the Belfast Agreement was dramatically underlined yesterday when the Taoiseach called on the IRA to declare its war was at an end. ail, Mr Ahern told the Dail research showed the unionist community had "a real fear" of sharing power with people who were, and might still be, associated with violence.
In a major speech in Belfast later today, Mr Blair - on his second outing in a week on the campaign trail in the North - is expected to directly address unionist concerns about the difficult issues of decommissioning paramilitary weapons, prisoner releases and Sinn Fein's participation in the proposed Northern Ireland Executive.
Downing Street has been engaged in a sustained behind-the-scenes attempt to win over Mr Donaldson since he deserted Mr David Trimble in the final hours of the negotiations which concluded the agreement on Good Friday. The Lagan Valley MP's late endorsement of the agreement would be an undoubted boost to Mr Trimble, given the impact thus far of a plainly better organised and more effective No campaign on "undecided" unionist voters.
However, like Mr Donaldson and Mr Trimble, Sinn Fein will carefully scrutinise Mr Blair's words for any evidence of a departure from the text of the multiparty agreement.
While it is thought Mr Blair is prepared to go some way to reassure unionists about his intention that decommissioning must be accomplished in the context of the agreement, British and unionist sources last night said privately they did not think he could do enough to lure Mr Donaldson back into the Trimble camp.
Among Mr Donaldson's own supporters there is also private acknowledgement that by meeting his demands Mr Blair could seriously endanger Sinn Fein's support for the agreement.
At their meeting at Stormont last Thursday night, Mr Donaldson is understood to have pressed Mr Blair to include in the main legislation effecting the agreement specific provision preventing prisoner releases or Sinn Fein participation in the Executive without the prior beginning of IRA weapons decommissioning. Sources last night confirmed that what they called "the Donaldson test" would entail specific legislative provision requiring a firm and clear declaration by the IRA that its war was over; actual and continuing decommissioning; the disbandment of its command and control structures; the assurance that there would be no continuation of the war "by proxy"; and the end of all so-called "punishment" beatings.
The suggestion also emerging in some unionist circles is that these decommissioning tests could be applied during the six-month period when the Assembly exists in "shadow" form pending the process of the legislation transferring powers to Belfast, and that the shadow Executive need not be formed until unionists are satisfied the IRA intends to decommission.
But Irish Government sources last night were adamant the agreement pre-supposes the establishment of all the proposed institutional structures speedily upon the completion of the Assembly elections at the end of June. And Sinn Fein sources said they did not believe the British government could impose conditions to the party's eligibility to participate beyond those set out in the agreement's text.
Under the agreement all parties affirmed their commitment to the total disarmament of all paramilitary organisations and their intention "to continue to work constructively and in good faith with the Independent Commission, and to use any influence they may have to achieve the decommissioning of all paramilitary arms within 2 years following the endorsement in referendums North and South of the Agreement, and in the context of the implementation of the overall settlement."
In the Commons yesterday Mr Trimble said there were increased fears Sinn Fein would "take the benefits" of the agreement "without accepting the matching obligations."
Meanwhile, Mr Blair spoke last night of his "revulsion" at the scenes of welcome for the Balcombe Street IRA prisoners at last Sunday's Sinn Fein ardfheis. Speaking on Ulster Television's Insight programme, Mr Blair said: "You feel a sense of revulsion at people who have murdered people, out there on a platform."
He said that if the Belfast Agreement was rejected in the referendum, "the British government will have to pick up the pieces again, it's our job to do that".