Cornish singer-songwriter Daisy Clark thought she would be performing at a wedding when invited to play a “confidential VIP gig” at the Eden Project in her home county on Friday night.

Instead, the 23-year-old lived out the “surreal” experience of playing for the president of the United States, the Prime Minister and other world leaders gathered for the G7 summit.

Clark was chosen to provide the entertainment while political heavyweights and their partners dined in the Biome at the Eden Project, an eco-park visitor attraction a short drive from summit headquarters.

She also saw the Queen, from a distance, before playing her set of originals and covers, followed by a “crazy” period of mingling with US President Joe Biden, First Lady Jill Biden and other dignitaries including Prime Minister Boris Johnson and wife Carrie, who is a big fan of her music.

Reflecting on the secrecy surrounding her booking, guitarist Clark said: “It was a VIP gig. The first thing I thought of was, a friend of mine who’s a musician actually played at someone’s wedding who was famous, and they had to do the whole NDA (non-disclosure agreement) thing and keeping it on the down low.

“Because I’d played at the Eden Project before and done weddings and events there like that, I thought it might be along those lines. Apparently not.”

The Newquay performer, who became a YouTube sensation four years ago when her innovative cover of Grease’s Hopelessly Devoted To You gained millions of views, said she had found out the true nature of her booking two days beforehand, leading to considerable nerves.

“I was pretty nervous in the day because everyone I went through on security who I met kept asking me if I was nervous, and kept saying to me ‘Oh this is a big gig!’,” she said.

“There was so much security and police around which in itself was very intimidating. But once I was in and setting up, my nerves settled a bit and I was actually okay when they were walking in because I couldn’t really see them properly from where I was stood.”

She was able to see her audience far more closely once she had finished her set of two originals and nine covers, which included The Beatles’ Yesterday, Fleetwood Mac’s Dreams and Belly Ache by Billie Eilish.

“I saw all the world leaders that were attending,” Clark said. “They actually invited me to go up to the table once I’d finished and they had finished their meal.

“The person that I properly had a conversation with was Jill Biden and President Joe Biden. They were very, very complimentary of my music. They really, really seemed to enjoy it and were just really lovely to me.

“Jill was saying that she wanted them all to stop talking at one point so she could hear the music properly. The president asked me my name, how old I was and he was just really complimentary. So that was amazing.

“Boris Johnson said thank-you for coming, and said how much they enjoyed the performance. Carrie was really, really complimentary. She loved it and was asking about the gigs I do down in Cornwall.”

Clark received a special, perhaps parochial, word of thanks from the Canadian Prime Minister.

“Justin Trudeau said he loved my cover of Complicated by Avril Lavigne. (She is) Canadian, obviously, so that was really nice,” said Clark, who saw the Queen through the window of the Biome before her performance.

“It was a once in a lifetime thing, but it was such a crazy experience. Not even the performing part, just being there and seeing all these people, and seeing the security. It was just very surreal, like I wasn’t meant to be there.

“I thought maybe I was picked because obviously I am from Cornwall, where the summit is being held.

“But when I spoke to an organiser they kind of said they’d been sending my music to the team at No 10 and that they had really loved it and wanted me to perform. So I think it was more them choosing me to play, which is crazy.”