Sinn Féin leader Gerry Adams has accused Northern Secretary Peter Hain of "pandering" to Democratic Unionist leader Ian Paisley.
Mr Adams told Sinn Féin's ard chomhairle meeting in Dublin on Saturday that there had been "no real progress" in the peace process since the Assembly met last month, for the first time in over three years.
"The British government needs to stop changing their minds every time Ian Paisley demands it," he said.
He confirmed that party chief negotiator Martin McGuinness, MP for Fermanagh and South Tyrone Michelle Gildernew and Newry and Armagh MP Conor Murphy would represent Sinn Féin on the special committee for restoring devolution, which will hold its first meeting in Stormont today.
The committee will also be attended by the DUP, UUP, SDLP and Alliance Party.
The SDLP will be represented by party leader Mark Durkan, deputy leader Alasdair McDonnell and senior negotiator, Seán Farren.
However, a party spokesman said yesterday that it had reserved the right to change its representatives on the committee, depending on the matters being discussed.
The Alliance Party will be represented by leader David Ford and deputy leader Naomi Long.
Chief negotiator Alan McFarland, Assembly group deputy leader Danny Kennedy and Michael McGimpsey will make up the Ulster Unionist delegation. No-one from the DUP was available to confirm which of its party members would join the committee.
DUP leader Dr Paisley had threatened to boycott the committee meeting if Mr Hain did not change his decision to have no debates at the Assembly this week.
Mr Hain then agreed that a debate would take place today on matters including industrial derating and the proposed reform of local government in the North under the Review of Public Administration.
Meanwhile, PUP leader David Ervine has defended Ulster Unionist leader Sir Reg Empey for his controversial Stormont alliance with the UVF-linked party.
Mr Ervine told Radio Ulster's Inside Politics programme that the alliance could work if given a chance and accused opponents of the link-up of prejudice against working-class Protestants.
"It is almost a form of racism. An IRA man can change, a peeler [policeman] can change but a Protestant working class man cannot change . . . It will work if Reg can be left alone . . . the prizes to be won are very special prizes."
Ms Long of the Alliance Party said she did not want to criticise Sir Reg for his attempts to broker a peace.
However, she added: "The commitment enshrined in the Good Friday agreement to only peaceful and democratic means should be applied consistently."
The British government declared last September that it "no longer recognised" the UVF's ceasefire.