Theresa Villiers says Westminster welfare plan unrealistic
The secretary of state has said the prospect of Westminster taking powers to legislate for welfare changes in NI is not realistic.
First Minister Peter Robinson suggested devolved powers for social welfare could be handed back if the Stormont parties failed to reach agreement.
Sinn Féin and the SDLP are currently refusing to support the changes.
Ms Villiers described the idea as hugely controversial.
"It's the current government's approach that any changes to the devolution settlement have to be broadly supported across the political parties, across the community, so I'm afraid on welfare reform, I'd love to see progress on this, but I think the progress in getting it through has to come through agreement between the political parties and adopting it at Stormont," she said.
The welfare reform bill, if implemented, would largely introduce measures already introduced elsewhere in the UK.
Mr Robinson told the BBC's The View on Thursday that a package had been discussed by himself and Martin McGuinness last May, but the deputy first minister could not sell it to his party.
The first minister said the package contained ways to help alleviate the effects of reform.
He said it had failed because Mr McGuinness had been unable to sell it to senior Sinn Féin members of the Irish parliament.
Mr Robinson said the Sinn Féin leader Gerry Adams had a very negative influence on the party's team in the Northern Ireland Executive.
In response, Mr McGuinness said Mr Robinson had "crossed the line" by saying they had reached agreement on welfare reform.
The deputy first minister said Mr Robinson's version of events was not true.
He said some of the first minister's comments in relation to the discussions that took place between them and other Sinn Féin and DUP negotiators on the issue of welfare cuts bore "no reality to what happened at the time".
Mr Robinson, the DUP leader, said in response to Mr McGuinness' comments: "I made it very clear in the interview that no deal is done until we get the support of our parties, that we were all comfortable enough to go with the package to our parties.
"That's the position that I outlined, it's the position that I stand over. Indeed in terms of them not being able to get their party over the line, why on earth would he have brought me in on a Saturday afternoon if there hadn't been some exceptional set of circumstances."