British officials are preparing to welcome Joe Biden to the UK for a State Visit next year.
The US President is understood to want to come to Britain to mark the 25th anniversary of the Good Friday Agreement which brought peace to Northern Ireland.
The trip could be the first time King Charles III welcomes a fellow Head of State to the UK for an official visit.
No date has been set but the trip is pencilled in to coincide with the anniversary of the peace pact that ended 30 years of violence in the province.
A senior diplomatic source said: “If you look at the calendar you will conclude that next year might be an obvious reason to visit Europe, if things come good.”
Whether the trip is technically a “State Visit” will depend on the date of King Charles’ Coronation - he can only host a State Visit once he has been officially crowned, which could take months.
One of Mr Biden’s predecessors as a Democratic President, Bill Clinton, visited Belfast in 1995 where he was mobbed by fans.
He stayed at the Europa Hotel which, during the Troubles, was known as the “most bombed hotel in Europe”. It was bombed 36 times during the conflict.
Mr Biden has repeatedly highlighted his Irish roots, which stretch from the Cooley peninsula on the east coast of Ireland to the town of Ballina in the west.
The trip could bolster his re-election campaign if he chooses to run again for the White House.
Images of the President being welcomed to the UK by the King would be beamed around the US, boosting his image among American viewers.
The last State Visit by a US President came over three days in June 2019 when Donald Trump and First Lady Melania landed on UK soil.
Mr Trump sparked fury by posing for a photograph at Blenheim Palace in an armchair used by heroic wartime leader Winston Churchill.
He also broke royal and diplomatic protocol by walking in front of the Queen as they inspected troops from the Coldstream Guards at Windsor Castle.
The plan for a State Visit by Mr Biden piles pressure on the Government and EU to thrash out a solution to the post-Brexit Northern Ireland Protocol, which prevents a hard border with the Republic - the UK’s only land boundary with the bloc.
It effectively sets a six-month deadline to reach a compromise on the Protocol, which would then revive the Stormont Executive and Northern Ireland Assembly.
Unionists say the controversial arrangement has effectively drawn a frontier down the Irish Sea, hampering trade in goods between mainland Great Britain and Northern Ireland.
Border posts and Army watch towers were stripped away following the 1998 Good Friday Agreement.
The deal was signed at Stormont over Easter 1998 after marathon tense negotiations hosted by then Prime Minister Tony Blair.
The Labour leader was building on years of fragile diplomacy forged by his No10 predecessor John Major.
Sources revealed Mr Blair is still playing a key role behind the scenes, trying to explain to EU and US officials why the Protocol is such an issue.
The diplomatic source said: “Tony Blair has certainly been explaining to the Europeans and the Americans that the British Government have a real point on the trading aspects of the Northern Ireland Protocol.
“He has been explaining - in a way that only he can, given his role in the Good Friday Agreement - why there’s no danger, why it’s not about the Good Friday Agreement, it’s about communities.
“He certainly has been a helpful voice, and I think he will go on doing so.”
