Northern Ireland crisis talks adjourn in early hours
Brian Cowen and Gordon Brown have travelled to Hillsborough Castle
All parties involved in crisis talks over the transfer of policing and justice powers to the Northern Ireland Assembly have now left for the night.
Gordon Brown and Irish premier Brian Cowen have been brokering talks between the DUP and Sinn Fein to avert the collapse of power-sharing at Stormont.
They arrived at Hillsborough Castle on Monday in a bid to end the impasse.
Discussions lasted until the early hours and are due to resume between 0900 and 1000 GMT.
'Sword of Damocles'
Speaking as he left the talks, Ulster Unionist leader Sir Reg Empey said the two premiers were making a "big effort".
"They wouldn't be here if they didn't think the situation was serious, but equally we have been here before," he said.
"I have to stress conducting negotiations with the sword of Damocles hanging over your head is not the best way to do business."
He said they had made their position known and would wait to see if they were called back to the castle on Tuesday morning.
SDLP Deputy Leader Alasdair McDonnell said that aside from the issue of policing and justice the governments should address the "dysfunctionality" of the Northern Ireland Executive.
"We urged the prime minister and the taoiseach to ensure that since they've taken the bother to come here this time that they do it right that there is not a cobbled solution that breaks down again in six months time," he said.
Alliance Party leader David Ford said that they expected to take part in further talks on Tuesday morning.
"We are clearly at the point where engagement is happening and that is to be welcomed, but we are a long way from reaching an agreement at this stage," he said.
Rather than holding direct talks, the parties have been holding separate meetings with the two governments.
Mr Brown has postponed Tuesday's cabinet meeting until later in the week, and more talks are expected to be held in the morning.
Mark Simpson, BBC Ireland correspondent
There's no prospect of a return to full-scale violence, but there is a full-scale political crisis.
The arrival in Northern Ireland of the two prime ministers is a sure sign that trouble is brewing. The blunt reality is there's no sign yet of any progress being made in the talks.
The equation is pretty simple - no deal means no devolution.
If these talks don't succeed, it's difficult to see how the Stormont Assembly will survive.
The two prime ministers arrived in County Down amid concerns that the power-sharing government at Stormont could collapse.
Until now, the talks on devolving policing and justice have only involved the DUP and Sinn Fein, but late on Monday night they were joined by delegations from the Ulster Unionist Party, the nationalist SDLP and cross-community Alliance Party.
Taking a break from negotiations, Sinn Fein's Gerry Kelly told waiting reporters: "The issues are well-known - we can have them sorted out very quickly."
Speaking outside the talks, DUP MP Sammy Wilson said Sinn Fein had created a "contrived crisis".
"Despite the way it has been handled, we are still open to resolving the outstanding issues," he said.
"It makes it darn more difficult in this atmosphere of crisis to get some kind of resolution - these things are much better done by people sitting down calmly, seeing where the problems are and what compromises can be made."
The leader of the Progressive Unionist Party, Dawn Purvis, said she was hopeful of a resolution.
"I think the parties have been talking at each other as opposed to talking with each other and discussing issues, so you could liken the government and the prime minister as a marriage guidance counsellor coming in to try and sort out the relationship between the two," she said.
Sinn Fein and the Democratic Unionist Party - Northern Ireland's two biggest political parties - have been arguing for months over the transfer of policing and justice powers from Westminster to Stormont.
Sammy Wilson, DUP: "This is a contrived crisis"
Sinn Fein want the completion of devolution to happen as soon as possible, but the DUP argue there must be unionist "community confidence" before powers are put in the hands of local politicians.
The "confidence" issue causing most division is over the handling of parades.
The DUP wants to scrap the Parades Commission, which puts conditions on some of the most contentious marches, but Sinn Fein has accused them of giving the Orange Order a talks veto.
Northern Ireland Secretary Shaun Woodward said massive progress had been made over policing in the last year and the process was now at an "endgame".
Irish Foreign Minister Micheal Martin said the two governments were ready to help the parties.
The leaders cannot agree over the transfer of police powers to Stormont
"We'll do what we can to bring these issues over the line," he said.
Talks between the two parties intensified in recent weeks, before collapsing in acrimony last week.
If Sinn Fein were to decide Martin McGuinness should resign as deputy first minister, the joint nature of the roles of first and deputy first ministers would mean that DUP leader Peter Robinson would also be forced out of office, collapsing the executive.
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