Sinn Fein President Gerry Adams is due to hold talks with Northern Ireland Secretary Peter Hain to discuss the Stormont spy row.
Mr Adams said he had asked for the meeting following his party's expulsion of Denis Donaldson on Friday after he admitted being a British agent.
Mr Adams said he had spoken with Mr Hain by telephone on Saturday.
On Sunday, Mr Hain said both Sinn Fein and the DUP were wrong to suggest the government was involved in a cover-up.
However, Mr Adams said his party "were not alone in indentifying elements within the British system involved in a campaign to undermine the peace process".
"Senator George Mitchell, Chris Patten and even Hugh Orde have all spoken of those within the British system working against the peace process and the implementation of the Good Friday Agreement," he said.
"Despite the intrigues of these dissident elements, significant progress has been made.
"However, more would have been achieved, and more quickly but for their plotting."
SEQUENCE OF EVENTS
4 October 2002: Three men arrested following raid on Sinn Fein's Stormont office. Power-sharing executive collapses and government restores direct rule to NI a week later
8 December 2005: Charges against three men dropped "in the public interest"
16 December 2005: Sinn Fein says Denis Donaldson was a "British agent" and expels him from the party: he later says he worked as a spy since the 1980s
Government and police reject the party's claim raid was politically motivated
Sinn Fein chief negotiator Martin McGuinness said his party would be happy to see an inquiry into the affair.
"I don't have any problem whatsoever with an inquiry," Mr McGuinness told BBC News on Monday.
"I have listened very carefully to the unionists over the course of the weekend, saying there should be. We would have no difficulty with that at all."
The DUP's Ian Paisley Junior described the idea that the devolved institutions could be revived in the current climate as "a fool's hope".
BBC NI political editor Mark Devenport said: "Between them, Gerry Adams and Peter Hain should be privy to almost all the details about Stormontgate, but today's meeting promises to be a clash of radically different versions of the scandal.
"Mr Adams says Mr Hain must take whatever steps are necessary to rein in those who he calls wreckers within the British security system.
"But government sources say Mr Hain does not accept Mr Adams' analysis and is more inclined to believe the advice of the chief constable, which is that the IRA was involved in systematic intelligence gathering."
Mr Donaldson said he had been recruited in the 1980s as a paid agent and deeply regretted his activities.
Northern Ireland's power-sharing executive collapsed in October 2002 following the arrests of three men, including Mr Donaldson, who had headed the party's administration office at Stormont.
Charges against the three were dropped after the prosecution offered no evidence "in the public interest".
Government sources say Mr Hain does not accept SF's analysis
Unionists have said Mr Donaldson's statement proved the charges against all three were dropped "in a deal with the IRA" to secure decommissioning.
However, both the Northern Ireland Office and the Police Service of Northern Ireland have denied this.
On Friday, the Northern Ireland Office said it "completely rejected any allegation that the police operation in October 2002 was for any reason other than to prevent paramilitary intelligence gathering".
It said "the fact remains that a huge number of stolen documents were recovered by the police".
Police sources earlier reiterated that the "Stormontgate" affair began because "a paramilitary organisation was involved in the systematic gathering of information and targeting or individuals".
But Sinn Fein has always insisted there never was a spy ring, calling the whole business "a politically-motivated stunt to discredit republicans".