The devolution of policing and justice could be in jeopardy if the Ulster Unionists do not pledge their support, the DUP has warned.
Nigel Dodds said his party would be unable to proceed with the Hillsborough deal if there was no all party agreement when the matter is put to a cross-community assembly vote next week
“I don't think we would then see progress happening,” the DUP deputy leader told the BBC Inside Politics programme.
The Hillsborough Castle accord was agreed between Sinn Fein and the DUP after 10 days of talks chaired by the British and Irish governments.
It includes an April 12 date for devolving powers, dependent on a March 9 Assembly vote in favour of the move.
A separate working group has made recommendations on resolving the loyal order parading dispute to the Office of the First Minister and Deputy First Minister (OFMDFM).
The Ulster Unionists have consistently stated their opposition to the agreement amid claims that the Assembly must resolve outstanding issues like education and housing before the problem of policing be tackled.
Sir Reg Empey and his team were the only political party not to turn up to Hillsborough Castle when the deal was signed off by the British and Irish premiers last month.
Last night UUP chief whip Fred Cobain said the party’s position had not changed.
“As it stands we do not support it, but a week is a long time in politics,” he told the Belfast Telegraph. “We were told a number of months ago that community confidence was there. We were also told that Peter Robinson believed in this project with every sinew in his body and he has got the Assembly numbers to support it.
“I would have thought that if the leader of a party had negotiated a deal and had enough members to put it through the Assembly then why would you want to hand that veto over to somebody else?”
Mr Cobain also said his party would not support the selection of Alliance Party leader David Ford as a new justice minister.
The normal procedure of electing ministers using the D'Hondt mechanism would give the ministry to the SDLP and Mr Cobain said acting outside D'Hondt was “gerrymandering”.
The north Belfast representative said: “We have a dysfunctional executive that can’t deal with issues like education and housing. So, to parachute additional powers into that Assembly would be totally irresponsible.
“We also don’t agree with the way the DUP and Sinn Fein to allow David Ford to be justice minister and we won’t be voting for that.
“There are numerous issues that we need to resolve.”