Peter Robinson and Martin McGuinness are expected to push David Cameron again next week on the need for an improved cash package to save Stormont from collapse.
The First Minister and Deputy First Minister are due to speak to the Prime Minister at a meeting of the Joint Ministerial Committee in London on Monday, which brings the devolved administrations of Northern Ireland, Scotland and Wales together.
Though shocked and disappointed by Mr Cameron's loans offer, Stormont's five main parties returned to the talks table only a few hours after he flew back to London.
However, a deal even on the most urgent budget issues appeared no nearer. Instead, the main focus of their discussions, which are due to continue on Monday, was on dealing with the legacy of the past.
Sinn Fein poured scorn on Mr Cameron over his £1bn loans package. Mr McGuinness said: "In the 18 hours of his involvement in this negotiation David Cameron made little or no contribution other than to duck his responsibilities.
"There was no credible financial package on offer which would enable the Executive to protect front line public services or to deliver the type of peace and reconciliation work needed to stabilise the peace process.
"Instead, the British Government is wedded to a cuts agenda which no party here agreed to and which is already taking an horrendous toll on our public services and on the most vulnerable people in our society."
Within minutes of confirmation that Mr Cameron was leaving, Sinn Fein leader Gerry Adams tweeted: "2 Govts exiting after most amateurish ham-fisted episode I have ever been involved in."
Education Minister John O'Dowd said that to call the PM's offer "derisory" was being polite, and he labelled Mr Cameron a "penny-pinching accountant".
First Minister Mr Robinson used more measured language. "It is essential that all parties remain focused if they are serious about delivering for the people of Northern Ireland," he said. "The Government must also commit to work towards an outcome that allows us to advance a stronger economy and recognises the challenges specific to Northern Ireland."
He argued that Mr Cameron had not been "sufficiently challenged on what his bottom line is on financial issues" and would have had "more give" if he had seen that welfare reform was going to be resolved.
"The negotiations seriously underestimated the task in hand," the DUP leader added. "The process will continue, there is a job of work to do. The absence of the Prime Minister does not bring the work to an end. It is the responsibility of parties to get the job done."
However, Ulster Unionist leader Mike Nesbitt hit out: "It was clear the Prime Minister flew into Belfast expecting the DUP and Sinn Fein to lead the local parties to a financial agreement. His frustration was obvious. The DUP/Sinn Fein carve-up at the heart of our government simply failed again."
And SDLP negotiator Alex Attwood said all parties had been taken aback by how "shallow and inadequate" the response of Mr Cameron had been.
"People are disillusioned, if not alienated, from politics," Mr Attwood added.
David Cameron came here on Thursday warning that "the credibility and effectiveness" of the devolved institution was at stake and flew out on Friday morning saying there had been no agreement. His ears were still ringing from the insults being hurled at him by John O'Dowd of Sinn Fein.