King Charles and Queen Camilla make surprise appearance on American Idol

King Charles and Queen Camilla made a surprise appearance on American Idol with judges Lionel Richie and Katy Perry.

The newly-crowned royals walked in on the two singers as they held a livestream for the US talent show from a room in Windsor Castle.

It happened just after Richie and Perry performed at Sunday night's Coronation Concert, which saw a star-studded line-up play for a crowd of around 20,000 people.

Charles joked that he "just wanted to check how long you'll be using this room". He added: “Thank you so much for your brilliant performance, it’s a pleasure to have you both here. It’s a great treat to have you both here.”

Perry gave a few curtsies towards the King and Queen and asked: "Are we making too much noise?"

Richie said: “We understand there’s a party … you’re throwing the party right next door.”

Charles replied: “Ah you’ve heard about that. We better take you to that, but you are busy with all these other things.” Richie replied: “As soon as we finish, we’re coming to the party.”

The King and Queen's appearance was seen as a sign of their warm and longstanding relationships with Richie and Perry.

In 2020 Perry was appointed as an ambassador of the British Asian trust by Charles, who founded the charity, while Richie is an ambassador of the Prince's Trust.

Sunday night's concert was held the day after Britain's first coronation since 1953 - a gilded spectacle that saw Charles become the 40th monarch to be crowned at Westminster Abbey.

Other members of the royal family, including 8-year-old Princess Charlotte and Prince George, 9, waved Union flags along with a crowd of some 20,000 gathered on Windsor Castle's east terrace. Charlotte and her mother, Kate, the Princess of Wales, sang along as Perry, dressed in a gold foil ball gown, performed her hit “Roar.” Top Gun star Tom Cruise appeared in a recorded video message, saying: “Pilot to pilot. Your Majesty, you can be my wingman any time.”

The mixed program also saw performances by the Royal Ballet, Nicole Scherzinger from the Pussycat Dolls, opera singer Andrea Bocelli and British band Take That. Even Miss Piggy and Kermit the Frog made an appearance, joking with the evening's host, Downton Abbey and Paddington star Hugh Bonneville.

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