A Sinn Fein delegation has met Prime Minister Tony Blair to discuss the government's blueprint for restoring devolution in Northern Ireland.
Sinn Fein's Martin McGuinness ruled out a shadow assembly
The talks between Mr Blair and Sinn Fein were held at Downing Street.
Afterwards SF's Martin McGuinness said his party would not take part in a shadow assembly at Stormont.
There is speculation a deadline for efforts to restore the assembly will be set by the British and Irish governments later this week.
Mr Blair and Irish Prime Minister Bertie Ahern are expected in Armagh city on Thursday to unveil their proposals for restoring the assembly.
The Sinn Fein delegation who met the prime minister at Downing Street included party president Gerry Adams, chief negotiator Martin McGuinness and North Belfast assembly member Gerry Kelly.
Speaking after Monday's talks, Mr McGuiness said: "We need to restore the political institutions and we need to do that immediately.
"We believe the sole task of the assembly is the formation of a power-sharing government as set out in the Good Friday Agreement and if the DUP refuse to allow this to happen then the governments have to move ahead."
Mr McGuinness said they had told the prime minister that the suggestion of a shadow assembly scrutinised by direct rule ministers was unacceptable to his party.
"We made it clear scrutiny committees are effectively nothing more than a DUP attempt to restore a unionist domination and that isn't acceptable."
At the weekend, DUP leader Ian Paisley said it was nonsense to predict that the Northern Ireland Executive would be formed by the end of November.
Political sources have told the BBC assembly members are to be called to Stormont on 15 May for a six-week period to try to form an executive.
Mr Paisley said the foundations for such decisions had not been laid.
Mr Paisley, whose party has suggested the formation of a shadow assembly, is due to meet Tony Blair on Tuesday.
However, SDLP leader Mark Durkan has said the DUP should not have a veto over devolved institutions.
Devolved government at Stormont was suspended in October 2002 following allegations of a republican spy ring at the Northern Ireland Office.
However, doubt was cast on that after a senior Sinn Fein official acquitted of involvement said he had been a British agent for 20 years and that there was no spy ring.