Talks to restore power-sharing ended without agreement last night as the DUP and Sinn Fein failed to meet the Secretary of State's latest deadline.
James Brokenshire is expected to make a statement in Westminster today on the negotiations as the British Government made plans to begin legislating for a budget for Northern Ireland in 12 days' time.
Party whips in the House of Commons have been asked to allow time on the week beginning November 13 for a Bill.
SDLP deputy leader Nichola Mallon claimed this would mark the beginning of direct rule from London and urged Sinn Fein and the DUP to "come clean" and publish their parties' talks papers so the public could decide who was the obstacle to a deal.
Talks sources said they did not believe agreement would be reached this week and said an Irish Language Act remained the major stumbling block to progress.
The DUP and Sinn Fein teams led by Arlene Foster and Gerry Adams were locked in negotiations yesterday.
However, sources said there was no significant movement on several issues and that "very real differences" remained between the two parties.
The talks ended around 8pm. The two parties will return to Stormont to resume discussions today.
Mr Brokenshire had extended his latest deadline by 24 hours to give the parties more time to compromise.
He had previously warned that if agreement wasn't reached by Monday, he would move to introduce a budget for Northern Ireland.
But he intervened to give them a new deadline of last night after reports of progress and "additional requests" the parties put to the British Government.
Stormont sources said Sinn Fein had asked Downing Street to release £150m to fund inquests for Troubles-related deaths. The package was promised as part of the Fresh Start Agreement but has so far not been made available.
The DUP and Sinn Fein last night remained tight-lipped on the state of negotiations, having pledged not to give a "running commentary" to the media.
The British Government said Mr Brokenshire was reflecting on progress at the talks and would brief MPs today.
Irish Foreign Minister Simon Coveney, who took part in the discussions, tweeted yesterday morning: "Important day for Northern Ireland - with political will and a willingness to work together on all sides there is a deal to be done."
Sinn Fein MLA Conor Murphy said the negotiations had entered a key phase. Speaking at Stormont, he said: "The talks are continuing and we are still in there trying to get the DUP to accept the rights enjoyed by citizens everywhere else on these islands.
"I'm not going to make any comment on those discussions because it would not be helpful at this stage.
"But I do want to take issue with those parties, including the SDLP, who are continually attacking Sinn Fein and who now demand a deal at any price. They should set out what they mean."
Mr Murphy asked "whose rights" the SDLP wanted to "abandon". He called on the party to clarify if it was "families waiting for inquests for 45 years, the LGBT community (or) those of us who demand recognition and acceptance of Irish cultural identity?"
The Newry and Armagh MLA added: "Sinn Fein is committed to securing rights for all of society and not just for one section of citizens."
The party has warned that when Mr Brokenshire moves to introduce a budget, it would mean the talks have failed.