The party last week listed the appointment of Lord Carlile to the job of reviewing MI5's operations in the North as one of the gains it made in negotiations with the British.

It comes as Sinn Féin met yesterday to discuss holding a special ard fheis to endorse the Police Service of Northern Ireland (PSNI). Gerry Adams has recommended that the party stage the ard fheis on 28 January, despite the DUP's refusal to agree to devolving policing and justice powers to the Assembly.

Lord Carlile's record makes him an unlikely candidate for Sinn Féin to endorse in the MI5 position. The Sunday Tribune can reveal that Carlile has supported Diplock courts in the North for each of the past five years, and has backed the detention for 90 days without trial of terrorist suspects in Britain, a practice which was vigorously opposed by civil liberties groups.

Carlile's annual review of MI5 will be in consultation with the Stormont first minister and deputy first minister, and future justice minister. This development was one of seven "advances" outlined by Sinn Féin policing spokesman Gerry Kelly last week.

The SDLP and former mainstream republicans have expressed amazement at what Sinn Féin settled for in its negotiations with the British on MI5's future role in the North.

SDLP policing spokesman Alex Attwood said: "The SDLP has no desire to make it difficult for Sinn Féin to sign up to policing. However, Sinn Féin should be honest and admit it is colluding with the British to hide the fact that MI5 has been given an expanded role in the North with virtually no accountability. Under the Blair-Adams deal, Nuala O'Loan will not be able to investigate MI5."

Veteran north Antrim republican Laurence O'Neill, who recently resigned from Sinn Féin, said Gerry Kelly was talking "pure nonsense" when he said last week's developments meant MI5 was now closer to leaving Ireland.

"If they are leaving, why have they just built a new multi-million pound base here?" O'Neill said.

Meanwhile, republican sources have told the Sunday Tribune that a relative of INLA hunger striker Patsy O'Hara is likely to stand against Sinn Féin in March's Assembly elections in Foyle on an antiPSNI and anti-Agreement ticket.

Willie Gallagher of the INLA's political wing, the Irish Republican Socialist Party, declined to comment on the matter. Gallagher's brother Paul, a former member of the mainstream republican movement from Strabane, is also planning to stand against Sinn Féin in the elections.