A deal on welfare reform which would help unlock the North's political impasse over public spending has been agreed by the parties in Belfast, Stormont sources said.
It is now up to British Prime Minister David Cameron to respond to the proposals, part of wider negotiations involving issues left unresolved from the peace process.
The power-sharing administration at Stormont faces £200 million cuts to its budget unless measures imposed by Westminster to reduce the benefits bill are introduced in Northern Ireland. Teachers, students and the health service could be badly affected, unions and business leaders have said.
Following ten weeks of discussions Sinn Féin deputy first minister Martin McGuinness and Foreign Affairs minister Charlie Flanagan struck an optimistic note.
Mr McGuinness tweeted: “A step change in negotiations!! Our team focused but more to do!!”
Mr Flanagan said: “Substantial progress has been made in negotiations over the past 24 hours. Intensive engagement continues.”
Dialogue has surrounded the multi-billion pound budget for the devolved administration at Stormont as well as issues left over from the peace process.
A dispute between the Democratic Unionists and Sinn Féin, the two largest parties, over welfare reforms imposed by Westminster has led to log jam and the threat of thousands of public sector job losses.
Republicans adamantly opposed benefits changes which they claimed targeted the most vulnerable.
Failure to implement them could cost the devolved ministerial Executive around £200 million in penalties to the block grant, producing dramatic public spending cuts, the DUP has pointed out.
The British and Irish Governments have led efforts to resolve the stand-off, with Northern Ireland Secretary Theresa Villiers and Mr Flanagan chairing negotiations at Stormont.
Mr Flanagan added: “We remain firmly of the view that a successful and comprehensive outcome to this process will be in the best interests of the people of this island and are working to that end.”
The DUP and Sinn Féin have also been at odds over how to tackle contentious parades, flags and the legacy of past killings.
The negotiations ended without agreement last Friday despite the presence of Taoiseach Enda Kenny and Prime Minister David Cameron
Mr Cameron offered the Northern Ireland parties what he said was almost £1 billion of extra spending power. The DUP and Sinn Féin rejected the proposal as not good enough.
DUP enterprise minister Arlene Foster has said the consequences for the political process of not striking a deal could be dire.