understands the vital role he and the monarchy play in UK diplomacy, a source has said. Last week, to US President , inviting him to visit the UK for an unprecedented second state visit.

The offer, presented at the outset of Prime Minister visit to the White House, played a key role in ensuring that the first meeting between the new Labour and Republican administrations was successful. Yesterday, hosted Ukrainian President following his with and Vice-President JD Vance on Friday. And today, , as the outgoing leader faces pressure of his own from the United States.

According to a source, the King is "very conscious" of his global responsibility and unique diplomatic role and determined to put that to use.

The source told PA News Agency: "It has been six days of royal diplomacy at its most delicate, deliberate and nuanced.

"His Majesty is very conscious of his responsibility globally, regionally and nationally - and passionately engaged in all the detail."

The source added: "As a global statesman and a head of state for both the UK and Canada, the King's role is highly significant, and His Majesty is determined to play his part, within appropriate parameters.

"His role by necessity and constitutional obligation is to offer symbolic gestures, rather than express comment."

Providing an insight into the two meetings, the source described them as being "routine but highly significant, given the global context".

has stated on numerous occasions that he would like the US to incorporate Canada within its borders, making it the 51st state, a claim widely criticised.

Details of what is discussed at private audiences are not shared by Buckingham Palace, but it is understood the challenges facing , for which the King is the head of State, were high on the agenda, as was support for .

As a constitutional monarch, is required to remain politically neutral, but he is able to advise and warn ministers and Prime Ministers, as his mother did for decades.