A bipartisan group of 21 members of the US Congress, led by New York representative Tom Suozzi, have written to Mr Blinken to express their concern at “the continual undermining of the rule of law, Good Friday Agreement and the ongoing process of peace and reconciliation”.

Richard E. Neal, one of the signatories, said: “Like every political party on the island, we are strongly opposed to proposed UK legislation that would give amnesty to human rights abuses committed during the Troubles. I look forward to Secretary Blinken’s response.”

The letter, which is supported by Amnesty International, urged Mr Blinken to call on the UK government “to abandon this unilateral action and establish mechanisms to deal with the legacy issues of the past that will discharge the UK’s human rights obligations”.

Grainne Teggart, Northern Ireland campaigns manager for Amnesty UK, said: “We strongly welcome this intervention from members of Congress, which adds to the noisy chorus of opposition to the UK government’s plans to permanently deny justice to victims of the Troubles.

“The UK government finds itself increasingly isolated on the international stage with its intent to sacrifice the rights of victims for the sake of protecting perpetrators of human rights abuses.

“We hope President Biden’s administration will heed the calls in this letter and publicly state their opposition to the UK government’s attempt to close down paths to justice forever.”