A former SDLP minister has backed Peter Robinson's claims that Sinn Fein pulled out of a deal on welfare reform after Gerry Adams scuppered the plan.
Former Social Development Minister Alex Attwood said that Martin McGuinness had reached a deal with the DUP leader on controversial welfare reforms.
Speaking on the BBC's Sunday Politics programme, the West Belfast MLA said that Mr Adams then "pulled the carpet from under Martin".
"There was a deal done between Robinson and McGuinness and Gerry Adams pulled the carpet from under Martin," the SDLP representative said.
"The deal was pulled by Gerry Adams and I was told that by senior people in and around the Irish Government, and I think that's probably corroboration," he added.
Mr Attwood's account backs claims made by First Minister Mr Robinson, who said the DUP had reached a deal with the Deputy First Minister on implementing welfare reforms almost a year ago.
The DUP leader suggested that the agreement could not be sold by Mr McGuinness to senior Sinn Fein colleagues in the Republic's parliament.
"It's the Dail team that drives it now," Mr Robinson had said.
But a furious Mr McGuinness then accused Mr Robinson of having "crossed the line" by claiming there had been a deal in place.
"I think it was a big mistake for him to do that," he said.
"Quite clearly some of the things that he said in relation to the discussions that took place between himself and myself on the issue of welfare cuts bear no reality to what happened at the time. I take umbrage at that."
Sinn Fein's John O'Dowd, who also appeared on yesterday's show, dismissed Mr Attwood's version of events and accused him of electioneering.
"Thankfully, Alex is not a member of Sinn Fein, so therefore he wouldn't be aware of any discussions going on within Sinn Fein, and thankfully none of the Irish Government parties are members of Sinn Fein either," he said.
Mr O'Dowd said the Assembly parties should present a "united front to the British Government" to secure the best deal on welfare reform.
And the Education Minister added that Mr McGuinness's leadership was "deeply respected" within Sinn Fein.
He went on to tell his 6,500 followers on Twitter: "Hardly a balanced report of the discussion on today's show.
"Alex Attwood's electioneering won't solve welfare reform."
Last week Peter Robinson warned that powers over benefits could be given back to Westminster if a deal is not reached – although Secretary of State Theresa Villiers described this as unrealistic. The DUP leader also sounded alarm bells over serious budget cuts Stormont would face if the Welfare Reform Bill was not passed. DUP Finance Minister Simon Hamilton claimed failure to introduce changes could cost the Executive £1bn in fines over five years and put 1,500 jobs at risk.