Revelations about the ­double agent within the IRA, codenamed ‘Stakeknife’, left the entire ­republican movement convulsed and traumatised, the confidential files have revealed.

Stakeknife was widely reported to have been Freddie Scappaticci, who headed the IRA’s feared internal security unit, nicknamed the “Nutting Squad”.

Scappaticci died on April 11, 2023, at the age of 77, having suffered a series of strokes.

He had fled Northern Ireland after it was claimed he was the informer known as Stakeknife and lived in witness protection.

A BBC investigative documentary revealed he is believed to have been involved in at least 17 murders.

The interim Kenova Report found that in 20 years as a double agent, more lives were lost than saved through the work of Stakeknife.

Army commander General Sir John Wilsey, described Stakeknife as “the golden egg” of military intelligence operatives.

The files revealed the entire republican movement was shocked in 2003 by the revelation that the UK government had an agent placed so highly within the IRA.

That year, both Irish and UK officials discussed precisely how widespread the damage was from the Stakeknife revelations.

Officials at a meeting of the British-­Irish Intergovernmental Conference (BIIGC) in London discussed the fallout in May 2003.

A steering note, written by an official at the government’s Anglo-Irish Division on May 19, 2003, details the topics likely to be discussed. Earlier that month, the UK government passed the necessary legislation to allow for the postponement of the Assembly elections in Northern Ireland.

“The secretary of state has discretion to set a date for elections prior to November 15,” the file noted.

The document added that, since a previous meeting at Farmleigh in Dublin on May 6 of that year, the political landscape had been “overtaken by the Stakeknife revelations and allegations”.

“These have convulsed the republican movement already traumatised by the failure of its statements and clarifications to meet the standard of clarity required by both governments and the British decision to postpone elections,” it said.

Bertie Ahern, the taoiseach at the time, indicated the previous week that “the Stakeknife controversy would be raised at this meeting”.