The Sinn Féin president, Mr Gerry Adams, will meet the PSNI Chief Constable, Mr Hugh Orde, in London this morning for the first time as hopes mount of a political breakthrough.
It is understood the meeting was arranged by Downing Street and will also involve the British Prime Minister, Mr Tony Blair. Sinn Féin said last night the party wanted to discuss demilitarisation.
It will be the first meeting between the Chief Constable and the president of Sinn Féin, which continues to boycott the new policing arrangements.
"There will be no discussion on policing issues at (the) meeting," the party chairman Mr Mitchel McLaughlin said last night.
However a spokeswoman for Mr Orde said the meeting was about policing in general and could also discuss wider community participation. The Taoiseach last night welcomed the meeting.
Also this morning the Rev Ian Paisley will lead a DUP delegation to meet Gen John de Chastelain to discuss IRA decommissioning amid positive signs on all sides that a deal to restore devolution to Stormont will soon be reached.
US President George Bush spoke to Mr Adams by telephone yesterday to offer US support for a political agreement. Mr Bush had a similar conversation with Dr Paisley on Friday.
Mr Adams said he told Mr Bush that Sinn Féin's objectives were to get DUP agreement and to ensure any deal is rooted in the Belfast Agreement.
"I told him that we may need the help of the White House to deliver these requirements," he said last night.
The intense political activity over the weekend has led a source to believe a deal to end political deadlock and 25 months of direct rule in Northern Ireland could be clinched as early as tomorrow following another meeting in Downing Street between Dr Paisley and Mr Blair.
However another informed source said that although a deal has "never been closer", more time may be necessary to "nail down all outstanding issues".
If Sinn Féin and the DUP agree, pictures will be taken of IRA decommissioning before Christmas, despite significant opposition within the Republican movement. Decommissioning could also be witnessed by two churchmen agreed by them.
The photographs will be held by Gen John de Chastelain, head of the international decommissioning body, and released to the public in March or April once a new Stormont Executive is established.
A report yesterday that the IRA was split over the decommissioning plans was dismissed by Sinn Féin.
A senior and reliable source said: "There is a one-word response to that - rubbish."
So far, however, the Government believes that the Sinn Féin leadership has not "been panicked" by the prospect of losing members to dissident republican groups.
The IRA leadership has recently moved to ensure that arms dumps, which are mostly in the Republic, are further protected from dissident hands.
The Assembly will approve the full membership of the Executive under the plan, rather than just the First and Deputy First Minister. The Executive would come into existence "in shadow form" in January, though ministers would not sit around a table until a final deal is done by March or April.
Though the change offers the DUP a veto, Government sources believe that it will not be abused since it gives them the opportunity to say that they did not vote for Sinn Féin ministers.
Neither Sinn Féin nor the DUP had presented "insurmountable" difficulties in their letters seeking clarification to the Governments' proposals.
"If the DUP were going to refuse it they would have done so before now," the Government source told The Irish Times last night.