The Conservative party has called on the British government to establish a full public inquiry into the 1972 IRA Claudy bombings.
Shadow secretary of state Quentin Davies made the call during Northern Ireland questions at Westminster yesterday.
East Derry DUP MP Gregory Campbell also tabled a motion calling for a detailed public inquiry.
Mr Davies said last month's police claim that former Conservative secretary of state William Whitelaw met Catholic Cardinal William Conway to discuss the case of a Catholic priest suspected of involvement pointed to a conspiracy.
Although Assistant Chief Constable Sam Kinkaid did not name the cleric – who is believed to be Fr Jim Chesney – he said police suspected the priest was involved.
Fr Chesney, who police say was never questioned in relation to the bombings, was moved from a south Derry parish to Co Donegal within months of the atrocity. He died in 1980.
Nine people were killed in the triple IRA bomb attack on the Co Derry village on July 31 1972.
During question time yesterday Mr Davies called on Secretary of State Paul Murphy to set up a public inquiry into the triple bombing "without fear or without favour".
He went on to say that the "sad impression" had been created that the government would spend more money and effort to find the truth when atrocities or cover-ups related to the nationalist community.
Mr Davies said documents were said to exist providing "direct evidence of a conspiracy to pervert the course of justice on the part of the then government and the Northern Ireland Office".
"On this side of the house we believe that the truth should come out, irrespective of who may have been involved in any cover-up, without fear or without favour," Mr Davies added.
Mr Murphy, who described the Claudy bombings as one of the most heinous crimes of the Troubles, said it would be inappropriate to comment while the police investigation continued.
He said the government was cooperating fully with the police investigation.
Mr Davies said the impression had been created that more attention was paid to finding the truth about atrocities in which nationalists were the victims
But Mr Murphy said the government made no distinction between nationalist and unionist victims of the Troubles.
He said he wanted the police investigation to be completed as quickly as possible, adding that there should be no cover-up in getting to the truth.
Earlier Mr Murphy told MPs that he hoped elections to the assembly on May 1 would go ahead.
"There is an intensive effort from every body in the political process in Northern Ireland to be able to ensure that we do restore the institutions," he said.
The central issue was to ensure "an exclusively peaceful means by which we engage in politics in Northern Ireland".
Mr Murphy said the collapse of trust had led to the suspension of the assembly. He agreed there must be a commitment to exclusively peaceful means.
