Prince William revealed mum's secret crush to Kevin Costner

William, Prince of Wales told Kevin Costner his mum Princess Diana had a secret crush on him.

'The Bodyguard' actor has revealed he was invited to meet the royal during a trip to the UK and during their chat, William opened up about his late mum Diana, Princess of Wales and told the movie star about his mother's feelings for him.

Costner told PEOPLE: "'I've never talked about this. But I can because of how I very much respect him, but I think it's a story worthwhile about him ...

"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' ...

"We met in this room where the chairs were still stacked on chairs. I'm sure there was somebody [waiting outside] but it was just someone I met. There was nobody else.

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

Costner then replied: "I know".

He added of William: "I'll never say what we talked about, but it was a very sweet thing. And we just chatted and we both broke away. And we never became pen pals or did anything like that. But I've had such fond memories of who he was, how I was approached, and what we talked about."

Costner had dealings with the princess prior to her death in a car crash in Paris in 1997 as he consulted her over a possible sequel to his 1992 film 'The Bodyguard' in which he played a man hired to protect a pop star, played by Whitney Houston.

The actor revealed he was put in touch with Diana by her then sister-in-law Sarah Ferguson, Duchess of York.

He told the magazine: "I was going to make a second one of 'Bodyguard'. There was a moment that that was really flying down the tracks, very quietly, because it's how I operate. I really keep things to myself ...

"'That's why when when it finally emerged that Princess Diana was going to maybe do that, we talked. It was so sweet.

"Sarah was the one that set this up. 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.

"She was going, 'No I'm going to make this happen, Kev'. And she did. I always respected her that she never inserted herself."