The Belfast High Court made the ruling relating to the Act, which would see inquests and civil actions relating to the Troubles era outlawed in future.

“We have been consistently clear the Legacy Act was unwanted, unworkable and contrary to European and international human rights standards,” said North Down MP Dr Farry.

“It therefore comes as no surprise the Act is unpicked at its first legal challenge. The Government has previously said the Independent Commission on Reconciliation and Information Recovery (ICRIR) as framed by the legislation would struggle to work without the immunity element of the Act. The ICRIR itself has said that it only wants to proceed on the basis of compliance with the ECHR.

“Alliance is calling on the UK Government to suspend implementation of the Legacy Act pending the outcome of further steps in the legal process. Crucially, the looming deadline for inquests should be lifted. Similarly, the ICRIR should not proceed with any further work.

“This Act and the continuing uncertainty around its implementation are causing untold and unjustifiable stress and anxiety for victims and survivors of Troubles incidents.

"Today’s ruling should therefore be a prelude to repeal of the Legacy Act and a replacement which has the confidence of local parties and especially victims.”