Although his official spokesman denied that the Prime Minister had threatened to suspend the Northern Ireland Assembly, Mr Blair warned that if the deadline was missed, it would be "looked at again".
Mr Blair made the threat after the Ulster Unionists, led by David Trimble, first Minister in the new Assembly, failed to attend a fresh round of talks at Downing Street yesterday.
The Unionists insist they had not intended to snub the Prime Minister's talks with Gerry Adams, Sinn Fein president, and John Hume, leader of the nationalist SDLP. They returned to Belfast last night for talks with officials from Sinn Fein and the SDLP.
But there was no hiding the fresh crisis facing the talks. Mr Blair's official spokesman said: "I would be misleading you if I said the talks had taken us much further forward, but it doesn't mean we haven't moved in the right direction."
All sides, including the Unionists, were adamant that the peace process was continuing, but there are pressures on the Sinn Fein negotiating team, led by Mr Adams, caused by slow progress over the Unionists' refusal to join a power sharing executive with Sinn Fein until the IRA decommissions its weapons
London and Dublin emphasised that the deadline set last weekend in marathon discussions with the parties at Downing Street will be made to stick. "We are serious about the deadline," said a British Government source. "The process continues and progress continues to be made."
The Irish Prime Minister, Bertie Ahern, a Manchester United fan, will be able to discuss the crisis with Mr Blair in London tomorrow at the FA Cup Final at Wembley. They are also attending a banquet at Chequers tomorrow evening.