Emergency legislation paving the way for direct rule to be reimposed on Northern Ireland was overwhelmingly backed by the House of Commons in London last night.
MPs voted by 352 to 11, a government majority of 341, to give a second reading to the Northern Ireland Bill in a division forced by rebel Labour backbenchers.
The Bill is due to become law by Friday.
The Northern Ireland Secretary, Mr Peter Mandelson, said he still hoped it would prove unnecessary to implement the Bill. Opening the debate, he warned that it was "pause or bust" for devolution. It was in no one's interests to see "these fragile institutions shatter irreversibly."
In a plea to paramilitaries to help break the logjam on decommissioning, Mr Mandelson stressed the important role this would have in confidence building.
"If the war is over, why do arms still need to be retained?" he asked. "If violence is a thing of the past, why can't weapons of violence be put permanently beyond use?"
The Deputy First Minister of Northern Ireland, Mr Seamus Mallon, said suspension should not happen if there was "any chance" of progress. Mr Mallon told MPs he shared their "profound disappointment and impatience" with the lack of decommissioning.
He also agreed with unionists who felt they had been "placed unfairly in a very difficult position."
But he added: "I ask them again to coolly assess, even at this point of difficulty, where their deepest interests lie.
"Suspension, by freezing the institutions, will also, I'm afraid, freeze the hope that we have of ever resolving this issue."
The people carrying guns would then carry with them the kind of influence that politics and politicians would not have.
He demanded of Mr Mandelson to know how a post-suspension review would be structured and who would chair it.
Holding up a copy of the agreement, Mr Mallon declared: "Let nothing we do in this House deviate from it or damage it.
"Let it not be played with before a review, during a review or afterwards because if we were, then we're playing not just with the present but the welfare of the future."
The First Minister and Ulster Unionist leader, Mr David Trimble, expressed disappointment.
Direct rule, he said, was the "third best" option. "Treating Northern Ireland properly is the second best, but I think the best of all is in fact to see devolution succeed within the UK, which is what we're trying to do through the Belfast Agreement and through the implementation of the Belfast Agreement."
Mr Trimble told the House: "People should not regard this as being a crisis - it's a difficulty.
"They should not regard it as being the end of the hopes the agreement engendered, but just as a problem that we will work through."
The shadow Northern Ireland secretary, Mr Andrew Mackay, backed the move to suspend the Executive but said it was "an extremely sad day for the people of Northern Ireland."
If the Assembly and Executive were suspended, it was "essential" that decommissioning began before they were reinstated, he declared.