The pair are set to meet on Thursday.
US President Joe Biden and British Prime Minister Boris Johnson are to meet in person for the first time as leaders on Thursday.
While there’s plenty on the agenda, one of the main talking points will be Brexit and its consequences in Northern Ireland.
Ahead of the talks with Johnson, Biden’s national security adviser Jake Sullivan warned the president harbours “very deep” concerns on the issues provoked by Brexit.
He said that Biden believes the post-Brexit Northern Ireland Protocol is “critical” to protecting the Good Friday Agreement, as the issues of checks on goods between the EU and Britain continues to cause problems.
The adviser told the BBC that negotiations between the two parties must continue.
“But whatever way they find to proceed must, at its core, fundamentally protect the gains of the Good Friday Agreement and not imperil that,” Sullivan said.
“And that is the message that President Biden will send when he is in Cornwall.”
Biden has also reportedly ordered US diplomats to criticise Johnson over his handling of Brexit and its effects on the Northern Ireland peace process.
A senior US diplomat is believed to have told Brexit Minister David Frost that the government is “inflaming” tensions in Ireland and Europe with its opposition to checks at ports in the province.
Sullivan would not answer whether a failure to ease the Northern Ireland concerns would affect any transatlantic trade deal but said that “our concern runs very deep on the Northern Ireland issue”.
Responding to Sullivan’s comments, Prime Minister Johnson said he was “very, very optimistic” about the situation and said there was an “easily doable” solution.
LISTEN: You Must Be Jokin’ with Aideen McQueen – Faith healers, Coolock craic and Gigging as Gaeilge
