Talks to save Stormont have taken a nosedive, with Martin McGuinness telling the Secretary of State to "put that in your pipe and smoke it" as he contradicted her figures on child poverty.
Ulster Unionist leader Mike Nesbitt said a meeting of the Executive parties, Theresa Villiers and the Irish Foreign Minister had been "frank" but "a total mess."
Ms Villiers was equally pessimist about the prospect of the talks - to implement last year's Stormont House Agreement and reform Northern Ireland's welfare system - succeeding.
"Regrettably, today's meeting took us no further forward," she said afterwards.
Ms Villiers' attempts to impose order on the talks earlier fell on deaf ears as she was challenged over statistics.
At one point the Sinn Fein Deputy First Minister treated the Conservative MP dismissively.
In one exchange, Mr McGuinness told the minister, "You can put that in your pipe and smoke it," as he challenged her child poverty statistics.
An unimpressed Ms Villiers said in a terse statement afterwards: "The prospects for a resolution of the welfare impasse look increasingly bleak. Time is running out. Implementation of the Stormont House Agreement (SHA) is the only way to avert a major crisis.
"The credibility and the future viability of the devolved institutions is now at stake. The choice rests with NI's political leaders."
The SHA reached last year committed Stormont to introduce welfare reforms, but with its own scheme to help claimants who lost out. Sinn Fein later withdrew support for the deal, saying that there clearly wouldn't be enough money to help everyone.
It also demanded to be told about any other planned cuts by Westminster, and for that to be factored in. London is committed to chopping a further £12.5bn off welfare spending across the UK.
The SHA also committed the Government to £700m in grants and loans for Stormont, much of it to cover a public sector redundancy scheme. These loans have now been made available in the hope that a solution to the welfare issue can be found later.
Yesterday there were few signs of optimism from participants. Mr Nesbitt felt nothing had been achieved.
"This lack of decision making is causing untold damage, not only to the vulnerable, but everyone," he said. "It was a very frank meeting at times, but it was posturing because everybody knows that in principle the Stormont House Agreement is the right thing to do."
Mr Nesbitt said the process was currently a "total mess" and does not envisage any movement until July 8 when the implications of the Chancellor's emergency budget would be known.
Sinn Fein has long demanded this information. This was made clear by Mr McGuinness to Ms Villiers yesterday.
Afterwards Conor Murphy - now back in Stormont - placed most of the blame for the situation on the Government and singled out Ms Villiers for criticism.
He denied the Government analysis that Northern Ireland has overspent and must make cutbacks like other UK regions if the economy is to recover.
"The financial crisis facing the Executive is a direct result of the Tory cuts to the block grant and threats by the British Government to the welfare state," the Sinn Fein MLA said.
He accused Ms Villiers of being "partisan" in her approach to the SHA, but insisted Sinn Fein was "still in resolution mode".
He called on "all political parties and civic society" to "stand together in the face of the austerity agenda of the Tory government."
The DUP Finance Minister, Simon Hamilton, said: "Today's meeting should have been about reviewing progress. Instead it focused on the abject failure of Sinn Fein and the SDLP to live up to and honour the commitments they made at Stormont House.
"No matter what their ideological motivations, it's high time the SDLP and Sinn Fein recognised the enormous damage their current dogmatic approach is inflicting on frontline services, the Northern Ireland economy and the reputation of the Executive."
Irish Foreign Minister Charlie Flanagan said: "Some difficult issues remain to be addressed - this will require resolute leadership."