SINN Féin's leader in the north Michelle O'Neill has said the DUP have failed to live up to previous agreements and are standing in the way of progressive policies.
A scheduled sitting of the Stormont Assembly to nominate new leading ministers was axed today after agreement between Sinn Fein and the DUP could not be reached.
"We are standing firm - previous agreements need to be implemented," Ms O'Neill said.
"We came at the negotiations with the right attitude, wanting to make the institutions work, wanting to deliver for all citizens.
"Unfortunately, the DUP maintained their position in relation to blocking equality, delivery of equality for citizens - that was the problem."
She said she was open to the suggestion that an independent chair be appointed to mediate new negotiations.
"There is a job of work to be done in the coming days," said the Sinn Fein MLA.
"We remain engaged, we remain committed to try and deal with the issues.
"But what is very clear and what we are very strong on is we will not return to the status quo."
Mrs O'Neill added: "We want these institutions to work. We want to work with the DUP, the UUP, the Alliance Party, the SDLP. We want to get back to the principles of the Good Friday Agreement and be true to genuine powersharing.
"If people want to do that then we are up for working with everybody."
During the negotiations, it is understood the DUP sought progress on implementing the Military Covenant in Northern Ireland as part of potential new legislation that would also offer more protections for both Irish and Ulster Scots speakers.
After 4pm if not deal is reached, focus will shift to Northern Ireland Secretary James Brokenshire.
Under legislation he is required to call another snap election if the deadline passes.
However, he is not obliged to set a poll date immediately, rather within a "reasonable period".
Mr Brokenshire may therefore delay calling an election to give a few more weeks to reach consensus.
