Mr Fred Scappaticci is not the British agent known as "Stakeknife", and categorically denies all allegations made against him, a solicitor's statement claimed yesterday.
Mr Michael Flanigan Solicitors, of the Falls Road in Belfast, released a statement it says was given to them by Mr Scappaticci which stridently denies allegations made about "Stakeknife".
Signed by the firm's principal, Mr Michael Flanigan, the statement says that Mr Scappaticci "denies each and every one of these allegations".
It claimed that he has never acted as an informer, has not been in contact with the security services, has not been taken into protective custody and has not received any payments from the security services. There was no reference to membership of any illegal organisation.
The statement alleged that Mr Scappaticci was in hiding as his life had been put in danger by the allegations which were "apparently emanating from the security forces and disseminated by the press".
It was further claimed that Mr Scappaticci was "an ordinary working man living in west Belfast and as such has no means at his disposal to combat this onslaught of false allegations". The solicitor said no further statements would be issued.
The issuing of the statement followed remarks made by Sinn Féin's Mr Gerry Kelly on Monday. In a short statement he said his party had been contacted by the Scappaticci family and that they had been advised by Sinn Féin to seek legal representation and to make a statement.
Yesterday's developments appear to show that advice had been followed. It came as the British Ministry of Defence said the military did not have Mr Scappaticci in custody.
However, there was no reference to the possibility that he could have been in contact with them of his own volition.
Republican sources continue to say that Mr Scappaticci has not left Northern Ireland while British sources confirm earlier claims that he did leave Belfast early on Sunday.
Sinn Féin restated accusations that the allegations came from British sources. The West Tyrone MP Mr Pat Doherty said yesterday: "The media reports at the weekend about an alleged agent all emanated from faceless elements within British military intelligence with all the resources of the British state behind them.
"They were aimed at a named individual who has no such means to counter these allegations and who has since denied these allegations.
"These allegations, speculation and disinformation come on the back of the Stevens Inquiry and revelations from the UVF and Michael Stone that loyalist death squads were manipulated and directed by FRU [the British army's intelligence wing - the Force Research Unit] and the Special Branch."
Mr Denis Bradley, vice-chairman of the North's Policing Board, said last night that nationalists were right to demand from the British a declaration that their intelligence war was over.
"There is a broad nationalist community which needs to know that their [the British] war is over - the war of intelligence, the war of using informers, the war of tapping . . . is also over and is coming to an end."