Nicole Kidman as Grace Kelly (left) and the real Grace Kelly
10/23/2012 AT 12:30 PM EDT
, who will play Princess Grace in an upcoming biopic
, has the seal of approval from at least one important figure in the late royal's life.
"First of all, I know Nicole Kidman. There is nobody more gorgeous," Lynn Wyatt, a close friend of Grace until her death in 1982
, told PEOPLE Monday at the 30th Anniversary Princess Grace Awards Gala hosted by the Princess Grace Foundation-USA at Cipriani 42nd Street.
"She's beautiful inside and out, and she's very sweet," Wyatt – a trustee of the foundation and an honoree Monday night – added of Kidman. "She's very nice – and she's caring. I think she would be perfect."
All that said, however, Wyatt does wistfully recall a moment when she realized her close friend, the former Grace Kelly, was especially breathtaking.
While acknowledging Kidman looks great dressed as the Princess in the movie Grace of Monaco
, Wyatt says, "But there was nobody like Princess Grace. I think it's flattering to have somebody play you like that – and of all people, Nicole would be the right one – but I remember I was at the Monte Carlo Beach Club, and she had all her hair up under this big hat, and I said, 'Excuse me, Grace, I'm staring at you.'
"You know, when you're good friends with someone you know them more inside than out, but her cheekbones, and just the way her eyes [looked], everything under that big hat, she was just so beautiful," Wyatt remembered. "I just said 'Grace, forgive me, but I'm staring at you.' And she just said, 'Oh, Lynn
The movie, set in 1962, is now filming in France and follows the Philadelphia-born star, who hit it big in Hollywood before she married Price Rainier of Monaco at a fairy-tale wedding in 1956.