Mr Stalker was speaking ahead of inquest proceedings which resume this week in Belfast into the deaths of five men and a youth, all unarmed, shot by a specialist squad of RUC officers over a five-week period in late 1982.

The ex-Deputy Chief Constable of Greater Manchester - who investigated allegations of an RUC shoot-to-kill policy - believes he could be called as a witness, but says he has not be contacted by the Coroner's Court, either officially or unofficially.

On Tuesday, Coroner John Leckey will begin re-examining the deaths of IRA men Eugene Toman, Gervaise McKerr, Sean Burns; INLA suspects Martin Grew and Roddy Carroll; and 17-year-old Catholic lad, Michael Tighe.

Mr Leckey will discuss with the lawyers representing the families and the PSNI the prospects of finally obtaining the 1985 Stalker Report in light of recent House of Lords ruling, which obliges the police to release all material to a coroner unless a minister issues a gagging order on security grounds.

It is known that in his report on the killings, John Stalker recommended the prosecutions of 11 police officers, ranging in rank from constable to chief superintendent.

He had plans to interview other "very senior RUC officers" when he was controversially removed from the inquiry and his damning report, seen only by senior police and government officials, has remained under lock and key.

In his 1988 book on the affair, Mr Stalker expressed the hope that one day the family of Michael Tighe would learn exactly how and why the 17-year-old died in a hail of police bullets.

Michael was shot in a police ambush on a hayshed near Craigavon where the IRA stored explosives. He had no security record or convictions and his family were paid compensation after his death.

An MI5 audio recording of the shooting has never been released and may be destroyed.

Mr Stalker said yesterday: "The family are entitled to know the truth. But after 25 years the truth is going to be hard to find."

He declined to speak further about the upcoming inquest as he believes he could be called as a witness.

He has been directing a rush of media inquiries to West Yorkshire Police, as it was that force's former chief constable, Colin Sampson, who completed the investigation he began.