The US government has added its voice to encourage the Northern Ireland parties to reach agreement in the Haass talks which must end today.
"It is time to fish or cut bait," Richard Haass, the talks chairman, said.
Dr Haass and Professor Meghan O'Sullivan, two former US diplomats, have been chairing complex discussions on flags, parading and how we deal with the legacy of the Troubles.
Amid hopes of a deal being struck by today's final deadline, there were signs last night that the talks were reaching a new sticking point on the definition of terrorism. The deadline for finishing will slip past lunchtime, instead of being at noon as announced on Saturday.
Last night Caitlin Hayden, the US National Security Council spokeswoman, issued a statement on behalf of the administration of Barack Obama.
She said: "Initiating these talks demonstrated the commitment of the parties and people of Northern Ireland to move forward on tough issues. We are confident that a solution can be reached if there is political will on all sides.
"We call upon the leadership of the five parties to make the compromises necessary to conclude an agreement now, one that would help heal the divisions that continue to stand between the people of Northern Ireland and the future they deserve."
The statement raises the pressure on participants, but the signs are that negotiations will continue until the last minute. Last night parties were issued with a sixth draft agreement, and were to discuss it this morning.
Shortly before he received the new draft, Mike Nesbitt, the Ulster Unionist leader, said the previous one was "80 to 90% over the line".
"So there's not a lot left, but what is left is serious from our point of view," he said. He told the Belfast Telegraph he had submitted a new document to Dr Haass and that his support could not be guaranteed unless his concerns were met.
The issue of defining terrorism has been raised by Innocent Victims United, a group representing 11,000 victims of republican violence. Its spokesman Kenny Donaldson rejected the Haass proposals as they stood.
He said: "The Haass talks process has conclusively failed to deliver this most basic fundamental from which a sound foundation could then have been built. Instead the process has provided succour for the warped narrative that what occurred in Northern Ireland was a 'conflict' or a 'war'."
The DUP did not take part in negotiations yesterday because it was Sunday. However on Saturday, party leader and First Minister Peter Robinson said parts of the proposed agreement were "unworkable" and he would work to improve on them.
While unionists struggled with the issues, nationalists appeared to be generally on board.
Sinn Fein leader Gerry Adams has voiced hope a deal can be done and appealed to talks participants to overcome differences.
Alex Attwood of the SDLP said: "We cannot now at the 11th hour allow that to unravel and be left with no outcome on the past. That would let so many people down."
The Secretary of State said she hoped all sides would show flexibility today. "From my many conversations on this over recent days, I am encouraged about the prospects for agreement, although some key issues are yet to be resolved, particularly on the past," Theresa Villiers said.
So what do the parties have to say about the Haass talks?
Deputy First Minister Martin McGuinness
“It would be a humiliation if Richard Haass and Meghan O’Sullivan left here on Monday against the backdrop of no agreement.”
DUP MLA Jeffrey Donaldson
“There are a number of significant issues that need to be resolved, particularly on parades and dealing with the past and so we’re determined to try and close the gap if we can.”
UUP leader Mike Nesbitt
“I would say 80, maybe even 90% of it is ready to go over the line. So there’s not a lot left, but what is left is serious from our point of view.”
“We have an agreement that is extraordinarily close to a final agreement that would leave both people as individuals, and society as a whole, far better off.”
The White House
“Talks led by independent chair Richard Haass with the five parties of the Northern Ireland Executive have reached a critical juncture... we now call upon the leadership of the five parties to make the compromises necessary to conclude an agreement now.”
Innocent Victims United spokesman Kenny Donaldson
“A deal should only be done when the contents of that deal have integrity. If, however, the deal is about placating and appeasing terrorism then it is a deal that must be walked away from.”
Six bodies or frameworks proposed by Haass and O'Sullivan... and what they would mean if they make a final agreement
* Historical Investigations Unit
The idea is that a Historical Investigations Unit would take over the work of the current Historical Enquiries Team, the PSNI unit set up in 2005 to investigate unsolved Troubles-related murders such as the Miami Showband massacre. The new unit would also take on the role of the Police Ombudsman's Office in pre-1998 investigations.
It is to be led by a trusted figure with relevant investigation or legal experience.
* Independent Commission for Information Retrieval
Its role is "truth recovery" that could give families answers on unsolved murders or incidents. Those co-operating would be offered a type of limited immunity, so they would not see their own evidence used against them.
However, that does not mean evidence gathered by separate means could not be used to prosecute. Thorny issues include levels of self-incrimination, the full extent of border cleansing, detention without trial, the treatment of prisoners, and the fate of the Disappeared like Jean McConville.
* Advisory group on patterns and themes
This will be made up of eight to 10 experts on the Northern Ireland conflict, both local and international.
Its role would be to review information and assess what, if any, patterns and themes can be gleaned.
The panel could be convened to learn the lessons of the past, like the recent protests over flying the Union flag at City Hall, and to watch out for future pressure points.
* New parading structure
This is the proposal to replace the Parades Commission. It will involve two new offices to deal with contentious and difficult decisions on parades.
The first is the Office for Parades, Select Commemoration and Related Protests. The second is the Authority for Public Events Adjudication. It will include seven members with a chair. A code of conduct acceptable to all sides is also required.
* Commission on Identity, Culture and Traditions
On flags and other issues, the plan is for a commission on identity, culture and traditions.
With no resolution expected on flags, the commission is a longer term process to look at flags and broader cultural issues. It will also look at the Irish language and a Bill of Rights, among other topics. A third party -- possibly the UK's Department of Culture, Arts and Leisure -- may be asked for proposals.
* Implementation and Reconciliation Group
Such a group would include victims' representatives and would monitor progress in the different strands addressing the past. It would monitor progress of any Haass/O'Sullivan agreement and keep up momentum on reconciliation between communities.