Sinn Fein and SDLP tonight welcomed Ulster Unionist party leader Mr David Trimble’s defeat of party rebels attempt to tie him to a deadline for achieving IRA disarmament.
The Northern Assembly First Minister won more than 56 per cent of the vote at a crucial ruling council meeting called by his anti-Agreement critics within the party.
Delegates voted 409 to 320 to back the leader's strategy aimed at securing the removal of all paramilitary weapons without imposing deadlines.
Nationalists tonight welcomed the result, saying it would help to stabilise the power-sharing Executive and the other institutions created by the Good Friday Agreement.
However, members of the `no' camp tonight vowed to continue their fight to change party policy, committing it to withdraw from the power-sharing Executive if the IRA does not get rid of its terrorist arsenal.
Despite being defeated, South Antrim MP Mr David Burnside insisted the vote had shown "very strong reservations" within the Unionist community.
He said: "We will be asking the Ulster Unionist Council at its AGM what advances we have made on British symbols.
The Ulster Unionist leader will now report back to the ruling council AGM on March 9th on further progress made towards decommissioning.
Speaking after the meeting, he said he was encouraged that his share of the vote had increased by 2 per cent from the last council meeting, adding it was a reflection of the progress that had been made on disarmament.
But he warned the government and nationalist parties not to ignore the very real concerns of unionists over the working of the Agreement.
"We will continue to be there striving to see what we consider to be the objectives of the agreement are realised properly, that we are being supported by the greater number of the party in so doing, but there are still very real concerns there.
"There is a clear need on the part of Government and other parties to realise that there is substance in those concerns," he added.
Welcoming today’s events, Sinn Fein chief whip Mr Alex Maskey said it was vital the parties worked together to consolidate the political process.
"All of us in the pro-Agreement parties now have a collective responsibility to build upon the progress made and move forward without further deadlines or ultimatums," he said.
A spokesman for the SDLP said it was clear those who had called the meeting were not interested in decommissioning but in strengthening their own positions within the UUP.
"We look forward to a period of stability and progress where the Agreement can be delivered in all its aspects," he said.
Norther Secretary of State Dr John Reid declined to comment but a Northern Ireland Office spokeswoman said: "The vote is a matter for the UUP but on many occasions the Secretary of State has made clear his respect for David Trimble's central role in the peace process."