Charles did not need to be asked twice when a guest at his Commonwealth reception, celebrating achievements of people from the “family of nations”, asked him to dance.

Freddy Tuilagi, 53, the eldest brother of the famous rugby-playing siblings, choreographed the King’s performance, holding out his arms across his chest and fluttering them, which Charles copied.

The King smiled as he moved and was watched by the Queen, and at one point Mr Tuilagi, an honorary consul with the Samoan High Commission, gave Charles a ceremonial fly swat, which was hung over his shoulder.

Mr Tuilagi said after the performance: “I told King I’m going to dance for you, when you go to Samoa, this is how they will dance.”

Asked to critique the King’s performance, he replied: “Good – he’s got the moves.”

Charles and Camilla hosted the St James’ Palace event ahead of their forthcoming trip to Australia and Samoa later his month, with the Pacific nation the setting for a major gathering of Commonwealth leaders.

England rugby player Joe Cokanasiga performed a symbolic gesture from his Fijian heritage and went down on one knee before the King and clapped three times, while the Queen chatted to pop icon Grace Jones about her hat from Treacy, a milliner they both love .

Among the guests representing the Commonwealth diaspora were Strictly Come Dancing judge Craig Revel Horwood, from Australia, and former judge Motsi Mabuse, born in South Africa, who also spoke to the Duchess of Edinburgh.

Revel Horwood was asked how Australians would react to their new King and Queen, and replied: “I think they’re going to receive an amazing reception, because Australia still likes to belong, otherwise it literally is going to be an island.

“I think it’s really wonderful to have the monarchy as head of state, so for me, it’s a great thing because I’m a royalist – and for a lot of people in Australia like my mum who loves the royals.”

The latest series of Strictly is up and running and Revel Horwood will be releasing his debut solo album called Revelations later this month.

He could not resist telling the King about it and said he could send him a copy.

Laughing, the judge said: “I did say my album comes out on the 8th of October, I just reminded him if he didn’t know.”

“I think he’ll probably prefer to listen to that than watching Strictly. I know the Queen loves Strictly, I don’t think the King is as fond.”