Joe Biden, the US Democratic presidential nominee, has said he would not allow the Good Friday Agreement to become a "casualty of Brexit" if he is elected president.
Mr Biden waded into the issue as Dominic Raab, Foreign Secretary, tried to reassure US politicians during a trip to Washington that Britain’s support for the peace accord with Northern Ireland was “absolute”.
"We can’t allow the Good Friday Agreement that brought peace to Northern Ireland to become a casualty of Brexit," tweeted the former vice-president, who is going up against President Donald Trump in November.
He warned that any trade deal between the US and UK "must be contingent upon respect for the agreement and preventing the return of a hard border."
Mr Biden’s comments following a meeting between Mr Raab and Nancy Pelosi, the top Democrat in the House of Representatives, who said if the UK “violates its international agreements” and Brexit “undermines the Good Friday accord”, there will be “absolutely no chance of a US-UK trade agreement passing the Congress."
Mrs Pelosi said the lower house of Congress, which is currently controlled by her party, would defend the 1998 agreement as a "beacon of hope for peace-loving people throughout the whole world".
Mr Raab is in on a charm offensive in Washington DC designed to ease concerns over Boris Johnson's recent Brexit talk moves.
Accusations that Mr Johnson is breaking international law and undermining Northern Irish peace by attempting to change parts of the Brexit Withdrawal Agreement have become wrapped up in UK-US trade deal talks in America.
The Internal Market Bill aims to make it easier to transport goods between the UK's four nations, and has raised concerns that a hard border will be imposed on the island of Ireland
Leading Democrats have been publicly warning that any undercutting of the Good Friday Agreement, a historic Northern Irish peace deal which ended years of hostilities, could see them veto the UK-US trade deal currently being negotiated.
The warnings carry political weight given that any trade deal will only become law when it is ratified by the two wings of the US Congress, the Senate and the House. The Democrats currently hold the majority in the House.
Asked whether the Johnson government had jeopardised a trade deal with its controversial attempts to alter aspects of the Withdrawal Agreement, Mr Raab put the blame on Brussels and repeated the UK’s support for the Good Friday Agreement.
“I think it’s a great opportunity for me to be clear that the threat to the Good Friday Agreement as it’s reflected in the Northern Ireland protocol has come from the EU’s politicisation of the issue and to be clear on how that's happened and why that’s happened,” Mr Raab said of his visit.
“Our commitment to the Good Friday Agreement and to avoid any extra infrastructure at the border between the North and the South is absolute.”
There were also positive words from Mr Raab’s US counterpart, Mike Pompeo, the US secretary of state,, who repeated US support for that agreement but also said he was “confident” the UK government would reach a solution that suited all parties.
Mr Pompeo said: “Yes, we trust the United Kingdom. I am confident they’ll get it right. We’ve made clear our view of the importance of the Good Friday agreements. We know the complexity of the situation. We’ve done what we can to provide assistance where we can.
“In the end this will be a set of decisions with respect to this that the UK makes. And I have great confidence that they will get this right in a way that treats everyone fairly and gets a good outcome for what it was the people of the UK voted for now several years back.”
Mr Raab’s trip to Washington DC makes him one of the few UK government ministers to visit during the coronavirus pandemic. Mr Johnson is still yet to visit the White House as prime minister more than a year after taking up the role.
Mr Raab’s tougher meeting, due to happen behind closed doors, was expected to be not with Mr Pompeo, a Donald Trump loyalist, but Ms Pelosi, who has in recent weeks not hidden her opposition to Mr Johnson’s recent Brexit manoeuvrings.
“What were they thinking?” Ms Pelosi recently asked about Mr Johnson’s move to revise the Withdrawal Agreement, adding: “Whatever it is, I hope they’re not thinking of a US-UK bilateral trade agreement.”
Four Democratic congressmen wrote a letter to Mr Johnson on Tuesday warning his latest move could have “disastrous consequences” for the Good Friday Agreement and may lead to a veto of the UK-US trade deal.
It has since emerged that a number of the signatories once made supportive comments or gestures about Gerry Adams, the former president of Sinn Féin and Irish Republican, including pushing for him to be invited to past presidential inaugurations.
Peter King, the New York congressman who signed the letter, is quoted in the Belfast Telegraph once saying in the 1980s: “If civilians are killed in an attack on a military installation it is certainly regrettable, but I will not morally blame the IRA for it.”
Trade deals talks between Britain and America remain on-going. It is very unlikely a deal will be reached and passed by the US Congress before the November 3 US election.