A group of prominent Irish Americans has called on the US President Joe Biden to 'stand up' for the Good Friday Agreement when he meets with the UK Prime Minister Boris Johnson this week.

The Ad Hoc Committee to Protect the Good Friday Agreement, which includes US political leaders and diplomats, has urged Mr Biden to use the meeting as an opportunity to inform Mr Johnson that he will be appointing a US Special Envoy to Northern Ireland.

Former US Congressman James Walsh, who is a co-chair of the Ad Hoc Committee, called on the US president to demonstrate America's ongoing commitment to protecting the Good Friday Agreement.

"We have been in touch with senior officials at the White House and have conveyed our views. We are increasingly concerned that the Good Friday Agreement is becoming collateral damage as a result of Brexit and the ongoing disputes over the Northern Ireland Protocol," Mr Walsh said.

US President Joe Biden will warn British Prime Minister Boris Johnson not to renege on the Northern Ireland Brexit deal when they meet for the first time at the G7 summit this week, The Times has reported, citing unidentified sources.

Preserving the delicate peace in Northern Ireland without allowing the United Kingdom a backdoor into the European Union's markets through the 500km Irish land border was one of the most difficult issues of the Brexit divorce.

The EU and Britain tried to solve the border riddle with the Northern Ireland Protocol of the Brexit agreement, which keeps the province in both the United Kingdom's customs territory and the EU's single market.

But unionists say it contravenes the Good Friday Agreement and London has said the Protocol is unsustainable in its current form after supplies of everyday goods to Northern Ireland were disrupted.

President Biden, who is proud of his Irish heritage, will use a meeting with Mr Johnson on Thursday to explicitly express US support for the Protocol.

He will also warn that the prospects of a US trade deal with the United Kingdom will be damaged if the situation remains unresolved, The Times said.

Mr Biden will also make clear to the European Union that he expects it to stop being "bureaucratic" and adopt a more flexible approach to the implementation of the agreement, the paper said.

David Frost, Britain's Brexit negotiator, is seeking to resolve the issues over the Brexit deal but the situation on the ground in terms of trade is "very difficult", Lucy Frazer, a government minister as Solicitor General for England and Wales, told Sky News.

Additional reporting: Reuters