By BBC News Online's political correspondent Nick Assinder.

The Northern Ireland peace deal is facing its greatest crisis yet after the government moved to reimpose direct rule on the province.

With the de Chastelain report confirming that the paramilitaries have given no ground on decommissioning, the process appeared to be heading towards collapse.

All parties were desperately playing for time in a last ditch attempt to break the impasse, but there were few signs that a breakthrough was imminent.

After a day of frantic diplomacy, Tony Blair and Irish Prime Minister Bertie Ahern planned to meet for eleventh hour talks on the situation aimed at finding a way out of the impasse.

Meanwhile, in the House of Commons, Northern Ireland Secretary Peter Mandelson left MPs in no doubt that peace process was on the verge of failure.

All or nothing

He warned that paramilitaries that their commitment to the Good Friday deal was "all or nothing".

And, with Ulster Unionist leader David Trimble ready to resign if a deal cannot be struck, he played for time.

He set yet another deadline for a commitment to decommissioning from the paramilitaries - which, to all intents and purposes means the IRA.

And he announced, to little surprise, that he was ready to reimpose direct rule if necessary.

But, as Tony Blair has learned, this is one issue over which he has only limited control.

He can facilitate the peace process but, when push comes to shove, it is the people on the ground who decide whether or not it works.

If Mr Mandelson is forced to reimpose rule from London it will represent a massive failure.

Labour has reaped huge rewards from the peace deal which was forged by the previous Tory government.

More than once it appeared on the verge of collapse but Tony Blair committed a huge amount of his time to salvaging it and without his personal intervention it is arguable the Good Friday Agreement would never have been signed.

Mr Mandelson's statement attempted to avert the looming crisis and, once again, delayed the moment of truth.

But for most MPs listening to the debate there seemed to be no resolution to the vital question about decommissioning.

Not for the first time, everyone is holding their breath in the hope that yet another deal can be struck before Northern Ireland is pitched back into bloodshed.