ITV News Political Correspondent Romilly Weeks explains what the row is about and why everyone's talking about sausages
The president’s national security adviser Jake Sullivan said it was "critical" the Good Friday agreement was not put in jeopardy through ongoing wrangles in the fallout from the Brexit trade deal.
He told the BBC: “President Biden believes and has said that the Northern Ireland Protocol, as part of the agreement between the UK and the European Union, is critical to ensuring that the spirit, promise and future of the Good Friday Agreement is protected.
“That being said, of course the UK and EU need to work out the specifics and the modalities on that, need to find some way to proceed that works both for the EU and the UK.
“But whatever way they find to proceed must, at its core, fundamentally protect the gains of the Good Friday Agreement and not imperil that.
“And that is the message that President Biden will send when he is in Cornwall."
The comments come after the EU threatened to launch a trade war against Britain if it fails to implement checks on goods entering Northern Ireland under the terms of the Brexit "divorce" settlement.
After talks in London ended without a breakthrough, European Commission vice-president Maros Sefcovic said patience with the UK was wearing "very, very thin".
Why isn't Boris Johnson sticking to his promise in the deal - checks on goods travelling between Northern Ireland and Great Britain?
His warning came after Brexit Minister Lord Frost refused to rule out the prospect that the UK could unilaterally delay imposing checks on British-made sausages and other chilled meats due to come into force at the end of the month.
Following three-and-a-half hours of discussions at Admiralty House, Lord Frost accused Brussels of adopting an "extremely purist" approach to the implementation of the Northern Ireland Protocol in the Withdrawal Agreement signed by Prime Minister Boris Johnson.
In a press conference afterwards, Mr Sefcovic insisted the EU has shown "enormous patience" in the face of "numerous and fundamental gaps" in the UK's compliance with the agreement.
He said that any further backtracking will be met with a resolute response.
"Of course, as you would understand, the fact that I mentioned that we are at a crossroads means that our patience really is wearing very, very thin, and therefore we have to assess all options we have at our disposal," he said."I was talking about the legal action, I was talking about arbitration, and of course I'm talking about the cross-retaliation."
Prime Minister Boris Johnson has insisted the G7 summit would not be overshadowed by his row with the European Union over the Brexit deal's impact on Northern Ireland.
"Well, I'm not worried about that," he told reporters in Cornwall.
"I think that this is an amazing opportunity for the world. It's a big moment.
"Don't forget, this is the first time in six months in office, almost, that Joe Biden, the US President, has been able to come overseas for a major trip, it's his first time on the European continent.
"It's the first time any of us really have been able to see each other face-to-face since the pandemic began.
"And, you know, the pandemic, let's face it, was a pretty scratchy period for the world.
"It was a pretty miserable period of competition and squabbling over PPE, and all sorts of things."
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