The Northern Ireland Affairs Committee is being urged to use all available powers to compel disclosure of a report on compensation for victims of IRA attacks linked to Libyan explosives.
Lawyers representing those bereaved and injured in a series of Troubles-related atrocities have written to MPs on the cross-party scrutiny body in a bid to intensify pressure on the British Government.
The move comes ahead of the latest stage in a legal bid by victims to sue Libya for supplying Semtex to the IRA.
Thirteen summons have been issued at the High Court in Belfast, aimed at forcing the PSNI to confirm the plastic explosive was used in deadly attacks during the conflict.
A hearing is due to take place later this month as part of wider attempts to secure permission to formally serve proceedings on the State of Libya.
Legal firm KRW Law is mounting the initiative on behalf of a number of victims, including Seamus Sullivan.
Mr Sullivan was injured in an attack at Falls Baths on the city's Falls Road in 1988. Two civilians and a British soldier were killed in the bombing.
Compensation claims are also being prepared in connection with the 1987 Remembrance Day bombing in Enniskillen, the so-called 'Good Samaritan' attack in Derry in 1988, and the Shankill Road bombing in Belfast in 1993.
The IRA received secret shipments of weapons from Libya during Muammar Gaddafi's time as dictator - including Semtex for several notorious bombings.
Previous efforts to secure payouts for victims of the paramilitary group's campaign have failed, despite Libyan assets having been frozen in the UK.
But claims are now being pursued through the courts in Northern Ireland for the first time.
An estimated 11 billion dollars was seized by the British government after the Gaddafi regime collapsed in 2011.
Earlier this week Shadow Northern Ireland Secretary Louise Haigh called on the Government to release a report into compensation for victims of IRA attacks involving Libyan-supplied weapons.
She claimed there had been an "intolerable delay" in disclosing the dossier authored and delivered by William Shawcross last year, leaving those who suffered feeling abandoned.
Solicitor Kevin Winters, of KRW Law, revealed the new attempts to break the impasse.
"The delay on the report's findings, allied to the ongoing refusal by police to release basic information, points to a wider systemic failing by the British Government," he claimed.
"That collective failing needs to be addressed now."
Mr Winters confirmed: "We have written to the Northern Ireland Affairs Committee to urge them to use all their powers to compel the Government to change its tune.
"In advance of the pending court hearings we also hope the PSNI will take a more flexible stance on the applications to release vital information that will help bring closure for many victims."