Just caught up in the moment, or a cunning ploy to reclaim the US?

Whatever King Charles and Queen Camilla’s motive, fans of the US talent show American Idol were in for a surprise when the couple appeared on the live stream of the show’s judges, Lionel Richie and Katy Perry, from Windsor Castle shortly after the two performed at the coronation concert.

Richie, 73, told the US television audience: “What a party, it was unbelievable. We’re trying to figure out what can we do to bring something different to the show, so I have a surprise.”

Perry then appeared shocked when the king and queen wandered into shot, with the king joking: “I just wanted to check how long you’ll be using this room for.”

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.” The queen said of their performance: “Fantastic, absolutely fantastic.”

Perry, 38, who executed a couple of curtsies, asked if they were making too much noise. And Richie said: “We understand there’s a party … you’re throwing the party right next door.”

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

The royals’ appearance was said to have been spontaneous, decided by the couple during the evening, and a sign of the longstanding relationship between the king and the two singers. Richie is an ambassador for the Prince’s Trust and Perry for the British Asian Trust, which was founded by the king.

Twenty thousand guests watched the concert at Windsor, where the Prince of Wales paid tribute to the king’s coronation “pledge of service”. Prince William took to the stage to speak about the pride he felt for his father, to highlight the king’s recognition of “people of all faiths, all backgrounds” and to say his grandmother Elizabeth II would have been proud. “Pa. We are all so proud of you,” he said.

Stars who performed included Paloma Faith and the closing act, Take That, along with cameos from Miss Piggy and Kermit the Frog from the Muppets. There were recorded tributes including from Tom Cruise.

Sunday night’s concert on BBC One was watched by an average UK audience of 10.1 million, according to overnight figures from the BBC. The event had a peak audience of 12.3 million, the corporation said. (The Guardian, UK)

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