Relatives of the Belfast solicitor, Pat Finucane, who was shot dead by loyalist paramilitaries in 1989, are to meet the Northern Secretary, Dr Mowlam, at Stormont this morning to press their case for a public inquiry into the killing.
Dr Mowlam pledged yesterday to bring Mr Finucane's killers to justice. "Be assured, I am not going to leave the issue alone," she said.
The matter is also likely to come up during the multi-party talks in Downing Street tomorrow hosted by the British Prime Minister and the Taoiseach.
In a confidential letter to Dr Mowlam on April 13th, published in today's Irish Times, the Minister of State at the Department of Foreign Affairs, Ms Liz O'Donnell, said "the case for a public inquiry into all the circumstances surrounding Mr Finucane's murder is compelling".
Ms O'Donnell's letter was accompanied by an 11-page document containing an assessment by Government officials in Dublin of a report into the Finucane case by the London-based human rights organisation, British-Irish Rights Watch (BIRW). An edited version of the assessment appears below.
In its assessment of the BIRW report, the Government concludes there is a "cogent case for a belief, on a prima facie basis, that elements in the security forces may have committed a range of serious crimes and breaches of the European Convention on Human Rights".
The assessment cites the grounds on which the Bloody Sunday probe was established, to support its case for a Finucane inquiry.
An RUC spokeswoman said last night: "It is clearly inappropriate to comment on leaked documents, particularly when they are couched in terms such as `strong suspicions' or `tending to confirm' unproven allegations.
"The central point is that the circumstances surrounding the murder of Mr Finucane are the subject of an investigation being conducted by Mr John Stevens and his team of outside investigators," she added.
Meanwhile, Dr Mowlam said: "I take the situation very, very seriously. I am determined that no option will be excluded." She wanted to see the new Stevens investigation result in a prosecution.
Mr Finucane was killed by gunmen from the Ulster Freedom Fighters, who burst into his Belfast home in 1989 and shot him in front of his wife and children.
The UN special rapporteur on the independence of judges and lawyers who reported last year on the Finucane killing, Mr Param Cumaraswamy, said the latest demands in Dublin for an investigation appeared to back him.
"I think the situation has come to a level now that it is going to be a little difficult for the UK government to refuse a judicial inquiry, particularly in the light of the brutal murder of Rosemary Nelson," he told BBC Radio Four.
But the Ulster Unionist security spokesman, Mr Ken Maginnis, speaking on the same programme, listed judges, lawyers and magistrates who, he said, had been killed by republicans: "There could not possibly have been collusion (by security forces) in those cases, so why would there have been collusion in the case of Pat Finucane?"
He added: "I totally repudiate those who killed Pat Finucane." But if Mr Finucane was killed by loyalists, it was no reason to assume there had been collusion. The Sinn Fein spokeswoman on policing, Ms Bairbre de Brun, has called for "a comprehensive investigation into all levels of collusion".