The Tories, led by William Hague, were threatening to vote against the third reading on Thursday of the Government bill to allow the early release of terrorist prisoners, after failing to get the assurances they were demanding.
This move could undermine the bipartisan approach to Northern Ireland before the crucial elections to the new Assembly on 25 June, but it was defended by the Tory spokesman on Northern Ireland, Andrew Mackay, who attacked the proposed legislation on the handing over of weapons as "a cop-out, weak and insufficient".
The Northern Ireland Office gave assurances that ministers would try to be "flexible" in the face of united criticism by the Ulster Unionists - led by David Trimble - and the Tories, before last night's committee stage of the Northern Ireland (Sentences) Bill. However, Downing Street officials made it clear that ministers "cannot rewrite the agreement."
At the centre of their concern was the promise by Tony Blair during the campaign for the referendum in Ulster that the release of prisoners would be linked to decommissioning of weapons. They claimed the Bill failed adequately to ensure that that promise would be fulfilled, in spite of assurances by Mo Mowlam, the Secretary of State for Northern Ireland, who will be given power under the bill to refuse to release prisoners who may continue to be involved in violence.
The Tories and the Ulster Unionists tabled an amendment calling for a commitment to "the total disarmament of all paramilitary organisations and the achievement of the decommissioning of all paramilitary arms, including any of its own, by 22nd May 2000".
Mr Mackay said: "We sought from the Prime Minister that the early release of terrorist prisoners would only occur if their paramilitary associates were full co-operating with the decommissioning."
He claimed that the Prime Minister had unequivocally given this assurance, and that there wouldn't have been a 71 per cent "Yes" vote in last month's referendum without this promise.
Conservatives insist that they are not going to be voting against the overall agreement if their amendments are not accepted, but they will be rejecting the legislation dealing with prisoners.
The Ulster Unionists' deputy leader, John Taylor, welcomed the Tories' stance. "I'm glad the Conservatives are now coming on board and supporting us to make sure that this legislation is made watertight. We want to ensure that what the Prime Minister said and what was in the agreement ... is spelt out clearly in the bill," he said.
The Liberal Democrats' Northern Ireland spokesman, Phil Willis, said: "This is the first real test of the Belfast agreement and it behoves all political parties to think very carefully before threatening the fragile peace."
Sinn Fein attacked Conservatives for threatening the legislation at a crucial stage of the peace process. Its chairman, Mitchel McLaughlin, said: "It is a quite disgraceful intervention at a very delicate stage in the entire process."
t Reforms to stamp out electoral malpractice in Northern Ireland, including the introduction of electronic voting cards, have received preliminary support from Dr Mowlam. However, changes will not be introduced before this month's elections to the new Northern Ireland Assembly.Reuse content