Travis Kelce says Prince William was 'the coolest' at Taylor Swift's London concert

Travis Kelce says Prince William was "the coolest motherf*****" at Taylor Swift's London gig.

The 34-year-old NFL star, who is dating the 'Anti-Hero' hitmaker, had the chance to meet the 42-year-old Prince of Wales at his girlfriend's Wembley Stadium show on June 21, and he is still raving about their exchange.

Speaking with his brother Jason on their 'New Heights With Jason and Travis Kelce' podcast, he said: "Dude, he was the coolest motherf*****."

Jason interjected and described the British royal as "awesome", while Travis added: "He was so cool."

The Kansas City Chiefs sportsman met Prince William and his children Prince George, 10, and Princess Charlotte, nine, backstage at the gig, but he wasn't sure what the right protocol was.

Travis admitted he didn't know whether to "bow", "curtsy", or "just be an American idiot and shake their hand".

He explained: "We wanted to be polite, especially on this side of the park."

He also joked that he's never seen his brother Jason "give someone that much respect" when he got the chance to talk to them at the gig.

He quipped: "You put your beer, like, 10 feet away from you."

Referencing a viral video of himself holding a beer cup between his teeth during one of Taylor's London gigs, Jason teased: "I didn't have it in my teeth when I met [Prince William]!"

He continued: "They were wonderful people, and that's what it's about. You know? Obviously, literally part of a monarchy, royalty. Yeah.

"Hard to be a down to earth human being, I would assume. But came off that way completely.”

Travis agreed, adding: "Very genuine, very cool."

Prince William - who celebrated his 42nd birthday on the same day as the show - shared a photo of himself, Prince George, Princess Charlotte and Taylor backstage, while Travis also got in for a group selfie.

On the official Prince and Princess of Wales Instagram account, he wrote: "Thank you @taylorswift for a great evening! #LondonTSTheErastour."

Sharing the snaps on her own account, Taylor quipped: "Happy Bday M8! London shows are off to a splendid start."