Kevin Costner has fond memories of Prince William.

The "Yellowstone" actor topped People's annual 100 Reasons to Love America issue. In an interview with the magazine, he recounted the time he met the future king. The Oscar winner was told that the heir apparent wanted to have a private meeting with him years ago, and he agreed.

"I happened to be in England, and I got this message that the prince would love to talk, and I said, 'What?'... and then I went, 'Okay,' "Costner told People.

Recalling the incident, the "Waterworld" star said he had nothing but "fond memories" of Prince William, how the royal approached him, and the things they discussed during their meeting. For him, Prince William was "very sweet" and "quite a young man."

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Prince William
Britain's Prince William, Prince of Wales reacts as he attends the second day of the Royal Ascot horse racing meeting, in Ascot, west of London, on June 19, 2024.
(Photo : BENJAMIN CREMEL/AFP via Getty Images)

During their chat, Prince William also shared that his late mom, Princess Diana, "fancied" the "Bodyguard" actor.

"We met in this room, and it was just us," Costner shared. "He walked up, and we shook hands... The first line out of his mouth was, 'You know, my mom kind of fancied you.'"

Years earlier, Costner had been in contact with Princess Diana for "The Bodyguard" sequel, his hit 1992 film opposite Whitney Houston

"There was a moment that that was really flying down the tracks, very quietly, because it's how I operate," Costner said.

In the same interview, Costner shared the potential plot of the "Bodyguard" sequel. The script was reportedly written at the time of her death in August 1997.

Prince William
Britain's Prince William, Prince of Wales reacts as he attends the second day of the Royal Ascot horse racing meeting, in Ascot, west of London, on June 19, 2024.
(Photo : BENJAMIN CREMEL/AFP via Getty Images)

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Costner is supposed to reprise his role as former Secret Service agent Frank Farmer, visiting Hong Kong to look after a prized racehorse. There, he will meet Princess Diana and be drawn into her orbit.

"He's on a plane, Princess Di's upfront, everyone has to get off the plane," Costner explained the sequel's plot, per Us Weekly. "Di goes off the plane first, she goes into Hong Kong because she's going to this [horse] race too."

Princess Diana
(Photo: Getty Images)
(Photo : Getty Images)

"Princess Di, I meet her the next day at a party and I'm looking at her like everybody else. And she finally walks over and goes, 'I know who you are!' And I said, 'What the f-k are you talking about?' She goes, 'I know you're here to watch over me.' And I said, 'No, I'm not actually. I'm watching over a horse,'" Costner continued. "In the story, she had broken with the royal family."

According to the actor, Sarah Ferguson introduced him to Princess Diana. Costner also found the Duchess of York "so sweet" for setting up the meeting between him and the late Princess of Wales.

"Sarah was very cool... when she could have been going, 'Well, I'm a princess too. What about me?' She didn't do that at all. Diana and I began to talk," he said.

Kevin Costner
Actor Kevin Costner attends the premiere of Disney's "McFarland, USA" at the El Capitan Theatre on February 9, 2015 in Hollywood, California.
(Photo : Jason Kempin/Getty Images)