Denis Murray: "Things aren't good at present, but at least all sides are talking"

But the UK and Irish government promised not to put the process on ice and leading politicians vowed afterwards to continue working for a deal.

After discussions including the Ulster Unionist and Sinn Fein, no significant progress appeared to have been made on the key issue of arms decommissioning.

Irish Prime Minister Bertie Ahern, who had chaired the talks alongside his UK counterpart Tony Blair, said meetings would resume next week.

He appealed to both parties to give ground and move away from their existing opposed position on arms.

"I don't expect either side to lose all but neither do I expect either to win all," he said.

"I am not asking either side to concede totally their position."

'No parking of agreement'

The leader of the SDLP leader, John Hume, who also attended the talks, said the positive outcome of the talks had been the commitment by the two governments that there would be "no parking of the agreement".

Alongside Seamus Mallon, who is Deputy First Minister of Northern Ireland, he put forward two new proposals to overcome the stalemate.

While the Ulster Unionists continue to demand decommissioning should begin immediately, Sinn Fein insists it has signed nothing committing it to do this.

Mr Mallon insisted this dispute would not be enough to destroy last year's Good Friday Agreement. "We are not going to allow it to crash," he said.

Sinn Fein warning

The talks began with a warning from Sinn Fein leader Gerry Adams that the Good Friday Agreement will be finished if demands for the IRA to handover its weapons continue.

The BBC's Denis Murray: Time is running out

"I think the Good Friday Agreement is in freefall," Mr Adams said.

"We are going into these talks positively and constructively.

"However, if the unionists stick to their position and the governments don't move to implement the agreement, then unfortunately this agreement is as good as dead."

'Process not in freefall'

However, Mr Trimble rejected Mr Adams' warning when he emerged from Downing Street after what he said were "positive" talks.

"I am sure the process is not in freefall and isn't going to be in freefall," he said.

He reiterated his belief that some way could be found to move the peace process on and fully implement the agreement.

Handover of weapons is holding up the peace process

"This is what people want. This is what people voted for by overwhelming margins in Northern Ireland and the Republic of Ireland and they are going to get it," he said.

"The problem is that people have so far failed to deliver on their obligations and we must see those obligations addressed in word and deed.

As the stand-off continues there has been speculation that if there is not a breakthrough soon the two governments could decide to suspend talks until the autumn rather than risk collapsing the agreement.

But a Downing Street spokesman has denied that this is an option. "That is simply wrong," he said. "We are not in the business of parking this process."

'Loyalists should lead'

Northern Ireland Correspondent Tom Coulter reports

Mr Trimble has also appealed to loyalist paramilitaries to break the decommissioning logjam.

He said the main problem was their refusal to play their part in last year's agreement by handing over weapons.