DR MO Mowlam, Labour's shadow Northern Ireland Secretary, will today warn the British government against any further procrastination" or "preconditions" should the IRA reinstate its ceasefire.
In a high profile speech in Belfast, Dr Mowlam will argue that "there should be an acknowledgment" of any IRA decision to call a ceasefire, and "a welcome to Sinn Fein into the talks process".
As the Tanaiste, Mr Spring, and the Secretary of State, Sir Patrick Mayhew, meet in London, Dr Mowlam will urge a compromise on the decommissioning issue to permit consideration of it and the political talks to proceed in parallel.
And in a significant refinement of Labour's position, Dr Mowlam will risk unionist outrage by declaring that "increasing cross Border co-operation to make the Border increasingly less relevant is simply common sense". Dr Mowlam describes this assertion as one of "four key principles" embodied in Labour policy.
Senior Ulster Unionists, encouraged by Mr Tony Blair's studied neutrality on the issue of the Union or Irish unity, have frequently hinted they could "do business" with a future Labour government.
But in her acknowledgment of a political purpose to cross Border co-operation and in her assessment of the obstacles in the way of inclusive all party negotiations Dr Mowlam's speech today is likely to be regarded as a definite tilt in the direction of nationalists.
And her insistence that "a compromise" must be found on the issue of decommissioning paramilitary weapons may well compound unionist suspicions triggered by Sir Patrick Mayhew's comments in the aftermath of last Thursday's elections.
Delivering the third in a series of John Smith memorial lectures, Dr Mowlam will insist Labour in office "would stand as firm as the present British and Irish governments" in calling for a renewal of the ceasefire.
But she will also say a ceasefire is called by the IRA there should be an acknowledgment of the IRA decision and a welcome to Sinn Fein into the talks process. Any procrastination, calls for validation, would rightly be seen as unfair and unjust calls for further preconditions to Sinn Fein's entry into talks and should be rejected. Why relive the problems and the log jams of the last 18 months?"
And in advance of a final commitment by the British government, Dr Mowlam supports a role for former senator George Mitchell, and his two colleagues on the International Body Gen John de Chastelain and Mr Harri Holkeri.
Dr Mowlam will say some of the difficulties in respect of decommissioning "are ... as a result of people or parties positioning themselves to avoid blame to save face".
Of conflicting unionist and Sinn Fein fears over decommissioning, Dr Mowlam will say. "These can only be addressed, to my mind, by all parties signing up to the six Mitchell principles which include a commitment to the total disarmament of all paramilitary organisations and then agreeing to work with a decommissioning body or committee which operates in parallel to the talks and reports regularly to them on what progress has been made.
"Both sides in the struggle over a format for decommissioning will not get what they want some compromise on both sides will be necessary."
Dr Mowlam will restate Labour's historical commitment to "unity by consent" and insist "that any change in the status of Northern Ireland can only come about through consent and by agreement between the two main traditions". But she will add that "progress can only come through the two governments working together to guarantee a settlement".