The Irish Government should trawl its documents archive to support the family of a solicitor murdered by Northern Ireland loyalists with state support, it was claimed.
The department of Taoiseach Enda Kenny and other key government organisations should examine their files anew in an attempt to help the family of Pat Finucane, Sinn Fein president Gerry Adams said.
British police and Army agents inside Northern Ireland's largest loyalist political gang, the Ulster Defence Association, had a key role in assassinating the north Belfast lawyer, a report from former UN war crimes investigator Sir Desmond de Silva said this week.
The Taoiseach has already reiterated his support for a full public inquiry into events surrounding the 1989 killing. Mr Adams said: "The Irish Government needs to shift into a higher gear in support of the family."
Mr Finucane, 38, was shot dead at his north Belfast home in February 1989 in front of his wife and three children. A new report into the killing was ordered by Prime Minister David Cameron late last year.
Sir Desmond concluded in his approximately 800-page review that members of the Royal Ulster Constabulary knew Mr Finucane was under threat and an officer even proposed the lawyer, who specialised in defending IRA suspects, as a target to UDA assassins. Sir Desmond also wrote that police and army handlers of agents within the West Belfast UDA "actively furthered and facilitated" his murder, mounting a "relentless attempt to defeat the ends of justice".
Prime Minister David Cameron has said the report contained shocking details, apologised to Mr Finucane's family and accepted that security force collusion took place. But he stopped short of ordering a full public inquiry which could compel key witnesses formerly of the security forces to give evidence. Mr Finucane's widow Geraldine has branded the latest review a whitewash.
Mr Adams urged the Taoiseach to "initiate an extensive examination of all documents in the Department of the Taoiseach, Foreign Affairs and Justice relating to the north and identify which could assist the family in refuting the British Government's effort to frustrate the Finucane family's demand for a public inquiry".
DUP parliamentary leader Nigel Dodds attacked Mr Kenny's remarks on an inquiry, urging Mr Cameron to stand by his stated position that there will be no more costly open-ended inquiries in Northern Ireland.
"Mr Kenny would be well advised to put his own house in order. He leads a Government which only recently attempted to limit the scope and time of the Smithwick Tribunal into Garda collusion with the Provisional IRA. Similarly, successive Irish governments have refused to reveal the extent of aid and support they provided to the terrorists of the IRA during the worst years of the Troubles. Mr Kenny is the very last person to be pressing the Prime Minister in any regard."