Seamus Ludlow, 47, was killed in “disputed circumstances” and his murder remains unsolved, according to lawyers representing the family.

They are seeking damages in relation to Mr Ludlow’s death, claiming collusion and negligence, in an effort to clarify the circumstances of his death and probe the failure of previous cross-border investigations.

Belfast firm KRW Law, representing Mr Ludlow’s family, said it had arranged a number of meetings with politicians from Sinn Féin andFianna Fáil to discuss the case.

Representations have also been made to the Government of Ireland, requesting both a meeting and an update in relation to the Government’s earlier decision not to establish a Commission of Investigation looking into the death.

Judge Henry Barron had previously recommended in a 2006 report that two Commissions of Investigation should be established to look into alleged missing documents and the conduct of the investigation by gardaí.

A statement published by KRW Law reads: “We find it disturbing that the Minister of Justice Frances Fitzgerald has gone against the recommendations of the most senior judge in the Irish State tasked with looking at these events, and this will be something we will be exploring further with the Irish government over the coming months.

“The civil action being launched in the North may, we hope, cause some traction in the South to deliver truth, justice and accountability for the family of Seamus Ludlow, 40 years after his death.”