The DUP and Sinn Féin travel to Leeds Castle in Kent tomorrow morning insistent that they are both prepared to sign off on a deal that would lead to the restoration of devolution.
The DUP's Mr Peter Robinson said there was the "tantalising" possibility of agreement, while his colleague, Assembly member Mr Gregory Campbell, said that the DUP was "up for a deal".
British and Irish government sources also say that while there are major obstacles to be surmounted, the parties were approaching the negotiations in a positive frame of mind.
"Things are going in the right direction," said a talks' insider.
The Sinn Féin president, Mr Gerry Adams, and the DUP deputy leader, Mr Peter Robinson, respectively at a press conference in Belfast yesterday and in an article in this edition of The Irish Times, said agreement was possible in the talks scheduled to conclude on Saturday at lunchtime.
Mr Adams said he could not absolutely predict how the negotiations would proceed, but he wanted to see a comprehensive deal.
"I can't call it. All I know is that if it were down to Sinn Féin it would have been sorted last October, last May, the year before, the year before, the year before. So we are there to try to make it work," he said.
Right up to the beginning of the talks senior British and Irish officials are in continuing talks with the main negotiators for Sinn Féin and the DUP to try to agree an agenda that would focus on the primary issues: ending paramilitarism, ensuring unionists will share power, policing, and also trying to find agreement over possible amendments to elements of the Belfast Agreement.
A key associate of Mr Adams stressed yesterday that resolving policing was a key component of a deal for Sinn Féin.
"Gerry Adams, in an article in The Irish Times in August, said policing will be the spine of the deal. That remains our position," the senior party figure added.
Mr Adams indicated that unionist concerns around IRA activity and decommissioning could be resolved, but he was adamant again yesterday that Sinn Féin would not tolerate any alteration to the fundamental architecture of the Belfast Agreement.
The DUP deputy leader Mr Robinson, in today's Irish Times, indicated that this could be one of the main obstacles to agreement. "The institutions of the Belfast Agreement failed to provide good government and must be changed," he writes.
Otherwise though, he made it clear that if the IRA ended activity and decommissioned, the DUP would share power with Sinn Féin.
"I believe that a number of factors combine to dangle before us the tantalising prospect of peace and stability, but the pace of progress is dependent on the willingness of the paramilitaries to leave the stage, and the ingenuity of the politicians in meeting the challenges and opportunities to establish a wholly democratic, fair and just society," Mr Robinson said.
His comments were echoed in a statement by Mr Gregory Campbell yesterday.
