Taylor Swift turned down an offer to perform at King Charles III‘s coronation concert in May, author Omid Scobie claimed in his new book, Endgame.

The royal correspondent did not give a reason for why the “Blank Space” singer, 33, passed on the regal invitation, but her Eras tour schedule gives a pretty telling hint.

Taylor was performing shows in Nashville’s Nissan Stadium on May 6, the day of the King’s coronation, as well as May 7, the date of the coronation concert.

While the Grammy winner was unable to jet across the pond to be part of the historic event, her former archenemy turned friend Katy Perry took the king up on his invitation. She sang her hits “Roar” and “Firework” for an audience of over 20,000 people at Windsor Castle, which included the monarch, wife Queen Camilla, Prince William and Princess Kate and their kids Prince George and Princess Charlotte.

Other artists who sang for the royal audience included Katy’s fellow American Idol judge Lionel Richie, Andrea Bocelli and the British pop group Take That.

Katy, 39, had a special tie to the king, telling Extra on April 24, “I’m an ambassador to one of his foundations for the British Asian trust, which primarily focuses on ending child trafficking, which is a huge issue of our time that people don’t talk enough about, and it just aligned with all my values. … He asked me to sing and it all aligned.”

The “Teenage Dream” artist told the crowd during her set, “I am so happy to be here with you people, I love you so much. I’m so happy to celebrate this whole weekend. I got to bring my mum, she is so happy to be here and we get to stay in Windsor Castle – no big deal.”

Taylor does have ties to the royal family. She performed at a 2013 fundraising gala for Centrepoint, a U.K. homeless charity which Prince William made his first patronage in 2005.

William, 41, recalled how the singer managed to get him on stage to take part in Jon Bon Jovi‘s performance of “Livin’ on a Prayer” at the benefit.

“To this day, I still do not know what came over me. Honestly, even now I’m cringing at what happened next, and I don’t understand why I gave in,” he told Apple Audio in 2021. “But, frankly, if Taylor Swift looks you in the eye, touches your arm, and says, ‘Come with me…’ I got up like a puppy and went, ‘Yeah, OK, that seems like a great idea. I’ll follow you.'”