Travis Kelce called Prince William a "motherf***er" on his podcast -- but also raved about him being the "coolest" kind.

In the 96th episode of the Kelce brothers' "New Heights" podcast, Travis and Jason spoke about the "Kelces' London Era," which included meeting Prince William's family at "The Eras Tour" at Wembley Stadium on June 21.

"We met royalty. There was royalty at the show. Got to meet Prince William. How 'bout that? Your Royal Highness... Dude, he was the coolest motherf***er. He was so cool," gushed the Kansas City Chiefs tight end.

RELATED: Jason And Travis Kelce Praise Prince William, Kate Middleton's Parenting After Taylor Swift 'Eras Tour' Meetup

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He also recalled how they were not sure how to act in front of the Duke of Cambridge and his children, Prince George and Princess Charlotte, when they met backstage.

"We were backstage meeting him. He was there with little George and Charlotte. They were an absolute delight to meet. [I] wasn't sure if I was supposed to like, bow to them, curtsy, [or] just be an American idiot and shake their hand," Travis recalled.

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"They specified because we weren't at like at an official royal event, we didn't need to bow or curtsy. But I did still address him as Your Royal Highness," Jason chimed in.

"I've never felt emasculated, and I did. That was the closest I've ever been."

Travis then joked that he's never seen his older brother "give someone that much respect."

RELATED: Taylor Swift Has 'Chosen A Side' In Prince Harry, Meghan Markle And Prince William Feud: Royal Commentator

The Superbowl champ also recalled when his girlfriend, Taylor Swift, and Prince William performed karaoke with Bon Jovi way back in 2013.

"Tay got him out of his shell, and sure enough, he went up there, and they ripped it. They said he had a blast, and I'm just like, I don't know if any other prince is doing that," he said.

"He was cool enough to be a part of it. That just shows how personable he is."

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Aside from meeting and gushing about the Prince of Wales, Travis made his "Eras Tour" debut in London and had his girlfriend "cracking up" and "swooning."

On Sunday, the footballer shocked the crowd when he joined his pop star girlfriend on stage during the "Tortured Poets Department" set.

He stepped out in a tuxedo and top hat and joined the skit before Taylor proceeded to her next number: "I Can Do It With A Broken Heart."

Jason Kelce and Travis Kelce

(Photo : YouTube/New Heights)