KATY Perry fans have gone wild over a key detail from the American Idol judge’s performance at King Charles III’s coronation ceremony.

Katy Perry, 38, sang at the Coronation Concert which featured performances from Lionel Richie, 73, and appearances from actors, Piers Brosnan, 69, Tom Cruise, 60, and more.

Katy Perry fans have gone wild over a key detail from the American Idol judge's performance at King Charles III's coronation ceremony.
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Katy Perry fans have gone wild over a key detail from the American Idol judge’s performance at King Charles III’s coronation ceremony.Credit: AFP

Katy formed at the Coronation Concert held at Windsor Castle
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Katy formed at the Coronation Concert held at Windsor CastleCredit: AP
Eight-year-old Princess Charlotte, the daughter of Prince William, 40, and Princess Kate, 41, was spotted singing along to Katy Perry’s ‘Roar’ at the Coronation Concert.

Charlotte waved the Union Jack next to her mom Kate as belted out the lyrics, “Louder than a lion, ’cause I am a champion!”

A video of Charlotte singing at the concert was posted on Twitter, where fans commented on the adorable moment and Katy Perry’s performance.

One person tweeted: “Ok I’m no royal watcher and ran across this by coincidence but that is freaking cute.”

A second fan commented: “Princess Charlotte’s sweet voice!!!”

“We loveeeeeuuuu #princesscharlotte,” added a thired.

A fourth Twitter user wrote: “At least one princess enjoyed herself!”

While a fifth commenter stated: “That was the cutest moment.”

Princess Charlotte was spotting singing along to Katy Perry's Roar as she sat next to her mom Kate
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Princess Charlotte was spotting singing along to Katy Perry’s Roar as she sat next to her mom KateCredit: Twitter/ RoyallyBelle_
Other fans focused on the Dark Horse singer’s performance, with one person writing: “Thank you @katyperry you smashed it! #CoronationConcert.”

Another fan commented: “Katy Perry is [a] knock out.”

While a third commenter tweeted: “Katie Perry stole the show! Glittering in gold.”

CORONATION CONCERT

King Charles, 74, danced alongside Queen Camilla and a jubilant crowd of 20,000 as Britain was treated to a spectacular coronation concert.

With the country continuing to celebrate Charles a one-off show at Windsor Castle saw the Royals on their feet as they boogied to Katy Perry, Lionel Richie, and Take That.

The two-hour spectacular featured music from the likes of Paloma Faith, appearances from Piers Brosnan and Tom Cruise, and a heartfelt speech from Prince William.

Lionel Richie sang his much-loved All Night Long as Charles and the Royals danced.

As mentioned, Katy Perry performed her hit Roar as Princess Charlotte sang along with her mom Kate.

Shen then dedicated her song Firework to Charles and the work they both do for The British Asian Trust.

Brit favorite Take That concluded the concert with a special feature from singer Calum Scott.

The King was on his feet waving a Union Jack as he danced along to the song Shine.

Prince George and Princess Charlotte were also up and waving their flags.

Closing the whole concert, the trio sang their 1995-hit Never Forget as the audience joined in.

Earlier in the show, Prince William delivered a speech and paid tribute to the late Queen.

William said she’s “keeping an eye on us” as he thanked Charles.

WILLIAM’S SPEECH

The Prince of Wales, 40, stepped onto the Union Flag stage decked out in red, white, and blue at Windsor Castle to huge cheers.

He explained how coronations are a “declaration of our hopes for the future”.

Speaking just over 24 hours after swearing allegiance to the new King, the heir to the throne described the Royal Family’s collective pride in his “Pa”.

As Kate beamed with pride, Will said: “I want to say a few words about my father, and why I believe this weekend is so important.

“But don’t worry, unlike Lionel, I won’t go on all night long.

“As my Grandmother said when she was crowned, coronations are a declaration of our hopes for the future.

“And I know she’s up there, fondly keeping an eye on us. She would be a proud mother.

“For all that celebrations are magnificent, at the heart of the pageantry is a simple message. Service.”

Wills referenced Charles’ message in his two-hour coronation yesterday.

He added: “My father’s first words on entering Westminster Abbey yesterday were a pledge of service.

“It was a pledge to continue to serve.

“Because for over 50 years, in every corner of the UK, across the Commonwealth, and around the world, he has dedicated himself to serve others, both current and future generations, and those whose memory must not be neglected.

“Pa, we are all so proud of you.”

A fan tweeted that Charlotte singing at the concert 'was the cutest moment'
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A fan tweeted that Charlotte singing at the concert ‘was the cutest moment’Credit: Twitter/ RoyallyBelle_

Another commented that 'Katie Perry stole the show! Glittering in gold'
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Another commented that ‘Katie Perry stole the show! Glittering in gold’Credit: PA