A pledge by Prime Minister Tony Blair to rebuild confidence in the Northern Ireland peace process has been welcomed by the Ulster Unionist leader, David Trimble.

Tony Blair made the promise after talks with the pro-Agreement parties and Irish premier Bertie Ahern at Hillsborough Castle, County Down, on Thursday.

David Trimble said he was pleased that action was going to be taken, but said he would wait and see exactly what it was, before making up his mind what to do about staying in government with Sinn Fein.

It is not clear exactly what Mr Blair intends to do, to show that the government is taking a tougher line on paramilitaries.

However, he said he would put forward proposals to the parties before parliament goes into recess on 24 July.

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Deputy First Minister Mark Durkan said the continuing instability was not helpful.

Mr Trimble requested Thursday's talks amid concerns over ongoing sectarian conflict in Belfast and allegations of continuing IRA activity at home and abroad.

Unionists say it is eroding support for the Good Friday Agreement among their supporters.

In transition

Speaking after the talks, the UUP leader said there had to be clearer consequences for paramilitaries who crossed the "red line", or there would be a "very serious problem indeed".

Mr Blair said it was important to recognise the peace process was a transition but the process must be kept moving.

The prime minister said all of the parties he had spoken to agreed to do everything they could to resolve the situation.

And he insisted Sinn Fein was serious about making the peace process work.

Bertie Ahern described the talks session as "good".

Sinn Fein maintains the allegations about the IRA are unproven and that the violence on the streets in recent weeks has been provoked by loyalists not republicans.

Party leader Gerry Adams insisted sanctions could not be taken against Sinn Fein under the terms of the Good Friday Agreement.

After the meeting, David Trimble briefed members of his party at a nearby hotel.

Speaking afterwards, MP Jeffrey Donaldson said his party leader had still not ruled out resigning as first minister if action was not taken against Sinn Fein.