British Prime Minister David Cameron stands accused of stonewalling repeated calls to open up files on the indiscriminate slaughter of 33 people including a pregnant woman.
As the Dail unanimously backed the latest demand for official documents to be disclosed on the no-warning 1974 Dublin/Monaghan bombings, Taoiseach Enda Kenny warned the case was central to ongoing reconciliation.
“Access by an independent international judicial figure to all original documents related to the Dublin/Monaghan bombings would bring substantial progress to the investigation of the atrocities so far,” he said.
“It would give the families of victims and survivors the surety at least of transparency and full disclosure.
“Without that, those affected understandably cannot come to terms with the suffering inflicted on them.”
Mr Kenny, who has repeatedly raised the case with his Downing Street counterpart, said it must be “adequately addressed if we are to achieve a genuinely reconciled society.”
It is the third time in the last eight years an all-party motion has been passed in Dublin demanding London allow access to files on the Dublin/Monaghan bombings.
Last week, rock stars U2 were among those who left wreaths at the memorial on Talbot Street in Dublin, where one of the three bombs in the capital exploded, in what was the bloodiest day of the Troubles.
It was addressed to Justice for the Forgotten, which campaigns for an investigation into alleged British state collusion in the atrocities.
Two others bombs were detonated on Parnell Street and South Leinster Street in the co-ordinated attacks in the middle of the evening rush hour on May 17.
About an hour and a half later the fourth no-warning bomb was set off in Monaghan town.
The attacks – which also injured hundreds – were blamed on the Ulster Volunteer Force.
Micheal Martin, leader of Fianna Fail, said a number of previous inquiries raised serious concerns about the non-cooperation of the British authorities.
“It is clear from the evidence that loyalist paramilitaries undertook the bloody deed, however the sophistication and co-ordination of the attacks raise serious issues around the potential orchestration of the explosions by elements of British security forces,” he said.
Mr Martin said Mr Cameron was “stonewalling” calls for information on “indiscriminate slaughter” that extinguished entire families with the pain still felt in silent homes across the country today.
“The ongoing refusal of Prime Minister Cameron to release the relevant documents is a fundamental barrier to achieving real closure,” he said.
“How long do we have to wait for a meaningful response from the British Prime Minster?”
He added: “The whole truth is needed.”
Gerry Adams, Sinn Fein leader, said Britain has never been open and honest about the role its intelligence services played in working with “unionist death squads”.
“It is now accepted that as a matter of fact that collusion was policy and administrative practice,” he said.
“This isn’t just a passive British government.
“This is an active effort to thwart efforts to get to the truth.”