Stars who have broken royal protocol: Ed Sheeran, Geri Halliwell-Horner, Joan Collins & more

Musician Ed Sheeran received an MBE in 2017 and amid all the excitement, made a mistake when greeting King Charles.

In a matey gesture, as they shook hands, Ed placed his hand on the royal's elbow, telling NBC: "Apparently, I did a big faux pas. I shook his hand and then grabbed it and you're not meant to do that."

Ed needn't worry too much, as fellow redhead Geri Horner was far more over-friendly when she met the future King back in the 1990s.

At the time, it was said that Ginger Spice pinched the royal's bottom, but she later told The Times she hadn't been quite that naughty. "Patting him on the bottom was against royal protocol but we're all human," she said. "It was the premiere of our film, Spice World, in the late 90s. There was a lot of nervous energy – young women, happy antics."

SEE: King Charles puts on a brave face at church service on anniversary of Queen's death - photos

Marvel actor Tom Hiddleston broke royal protocol in 2016 when he slung an arm around Queen Camilla, at the time the Duchess of Cornwall.

The thespian was pictured with his arm around the royal at a literary event. While it seemed over-familiar, Camilla had been friendly herself, telling Tom: "Sunday nights just aren't the same without you," referring to Tom's role in BBC drama The Night Manager, which was everywhere at the time,

Much-loved actress Joan Collins revealed that even the most famous of celebrities become starstruck around royalty.

In her 2023 memoir, Behind the Shoulder Pads: Tales I Tell My Friends, Joan shared that she forgot to curtsy when she met Princess Kate in 2022.

"Suddenly, a vision appeared in a red dress. Catherine, the Duchess of Cambridge, with her two young children in tow," Joan wrote. "'Hello, Joan,' she said sweetly, holding out her hand. 'Hello, ma'am,' I gulped, forgetting to curtsy."

Roger Federer has a close relationship with the royals, even teaching Prince George to play tennis, so it's only natural that he reacts with friendliness when he meets this.

His familiarity was clear during Wimbledon 2023 when he greeted Princess Kate by placing his hand on her back and leaning forward, as though he was going to kiss her cheek.

Anticipating his move, the Princess of Wales subtly moved backwards and gave the champ a nod instead.

Top Gun Maverick actor Miles Teller met the Prince and Princess of Wales at the premiere of his and Tom Cruise's film, and despite being told beforehand how to greet the royals, he forget upon their arrival.

"There’s a lot of etiquette and I had a sheet so I wouldn't [expletive] it up… [But] right off the bat I messed up."

"You're not supposed to extend your hand right off the bat unless they do. But I felt the vibe, so I'm like, 'I'm going in, I'm going in,'" Miles told Jimmy Fallon. "To their credit, they were very disarming. I was lost. Prince William's eyes… Kate was beautiful and cordial, but with William; I don't know, I blacked out."

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Lewis Hamilton has met with royalty on numerous occasions, and it seems the late Queen took his breaking of protocol in her stride. 

"I was excited [to meet the Queen] and started to talk to her. But she said, pointing to my left, 'No you speak that way first, and I'll speak this way and then I’ll come back to you'," Lewis recounted to Graham Norton.

Former First Lady Michelle Obama surprised royal watchers when she placed a friendly arm on the late Queen's back during a 2009 meeting.

While her matey move caused dismay, Barack Obama's wife wrote of the meeting in her memoir Becoming: "Forget that she sometimes wore a diamond crown and that I'd flown to London on a presidential jet; we were two tired ladies oppressed by our shoes.

"I then did what's instinctive to me anytime I feel connected to a new person, which is to express my feelings outwardly. I laid a hand affectionately across her shoulder."

It wasn’t until after their meeting that Michelle realised her gesture was in fact "deemed as an epic faux pas."

Reflecting on her actions, she added: "If I hadn’t done the proper thing at Buckingham Palace, I had at least done the human thing. I daresay the Queen was okay with it, too, because when I touched her, she only pulled closer, resting a gloved hand lightly on the small of my back."