SINN Féin has urged the secretary of state to call another election if Stormont's parties fail to resolve their differences by Friday.
Northern leader Michelle O'Neill indicated yesterday that there was little prospect of a deal but insisted her party was committed to the remainder of the negotiations.
DUP deputy leader Nigel Dodds accused republicans of not being serious about securing agreement.
The North Belfast MP claimed Sinn Féin was tabling new demands "on a daily basis", including pressing for post-Brexit special status for the north.
Breaking off from negotiations yesterday, Ms O'Neill said another Stormont election should be called if Good Friday's deadline passed without a deal.
"We have set out what we need to see delivery on and we need to see a different approach from the DUP and indeed from the British government," she said.
"But post-Friday I think it is over to the electorate to have their say about the future."
The Mid Ulster MLA said Sinn Féin wanted to make the devolved institutions work but they needed to "work for all our citizens".
DUP leader Arlene Foster questioned Sinn Féin's sincerity at the negotiating table.
"We did say to them that after some of the things they have said (recently) that we doubt they want a deal – that is very disappointing," the former first minister said.
"They are telling their people one thing and when they are in here they don't seem to want to move and to compromise and to create the circumstances where we can go back into government."
Mr Dodds said Sinn Féin's demands on "narrow partisan issues" such as Brexit were an example of republicans "preventing the formation of government".
But SDLP leader Colum Eastwood accused the DUP of failing to grasp that there "needs to be respect for each other's identity".
"At times, in many of the meetings, the DUP haven't quite grasped the fact that things have changed – they haven't quite grasped that if we just allow the assembly, the majority of the members in there, to decide a lot of those issues then we could get things moving forward," he said.
New Ulster Unionist leader Robin Swann said he was finding it difficult to remain positive.
"We are seeing little sign of progress but the Ulster Unionist Party is still here and want to get a deal by Friday because we believe it is achievable," he said.
Alliance deputy leader Stephen Farry said another election would "solve nothing".
"People have had their say and almost 65 per cent of the available voters said they wanted to see devolution up and running again," he said.
"Another election would solve nothing, except returning MLAs to talks about the same topics."
The main stumbling blocks after nearly five weeks of talks have been Irish language protections and how to deal with the toxic legacy of Troubles killings.
Secretary of State James Brokenshire indicated last Thursday that he would begin the legislative steps to either restore devolution or make the first moves toward direct rule over the Easter weekend.
Meanwhile, People Before Profit (PBP), who met Mr Brokenshire yesterday, said the talks "are going nowhere".
Gerry Carroll MLA said vulnerable groups should not be hit by the absence of a budget.
"If the minister has any sense, he should put immediate measures in place to ensure that no jobs or services are lost due to the failure of these talks. Youth groups should not be made to pay for the failures of politicians," he said.
