The meeting took place in London last month to shake hands on JP's proposed biopic on the life of Gayatri Devi, the wife of Man Singh, the last ruler of Jaipur.
The Rajmata's verdict? She absolutely loved Aishwarya Rai and has given her wholehearted support to JP's proposed film.
Aishwarya, in the thick of a hectic start-to-finish schedule of Jagmohan Mundra's "Provoked", is walking on air.
"I can't believe I'll be playing one of the most beautiful women in the world. To get to enact Gayatri Devi, and that too in a film by J.P. Dutta ... wait, let me pinch myself," she bursts out laughing.
Then she spills the details of the historic meeting.
"You know, it was Gayatri Devi's birthday when we met. My mom and she share the same birthday. It was a very special day for me. JP saab and I spoke with Gayatri Devi for a while. She gave her nod almost instantaneously," she told from London on telephone.
"I'm elated. But I'm also nervous. To play someone so legendary is a big responsibility. It's so strange. I'm right now playing a real-life character (the battered Sikh wife Kiranjit Ahluwalia in 'Provoked'). Then I'll go into another real-life character. But one that is completely different.
"Gayatri Devi has lived her life king-size... Or should I say, queen-sized? I hope I can do justice to her story... It is such a vast story. But I think JP saab will manage it quite well."
The jubilant J.P. Dutta adds: "My wife Bindiya (Goswami), Aishwarya and I went to wish Gayatri Devi on her birthday. She was very excited that everything was falling in place.
"I think she's very happy that Ash will be playing her. In fact, when the Rajmata and I had spoken earlier in Jaipur about a film on her life, I had mentioned Ash. She thoroughly approved of my choice."
Research work is on full-throttle. JP and his father, veteran writer-director O.P. Dutta, are in London working on the script.
"Gayatri Devi is willing to provide all the help possible. She'll introduce me to her friends, take me to the places relevant to her life. I need to get my script in place.
"Writing about her life isn't easy. I read her autobiography. And I can see I've a staggering task ahead. To recreate Gayatri Devi's life is to re-live almost the entire 20th century and a part of this century. The budget and the scope are immense.
"The Rajmata asked me how I'll manage to put her life together in one film. I told her, 'M'aam, there's a hand above guiding me. That hand has brought me this far. It'll take me through your life'. I've to get down to the script and see how much of it to get in. I'm getting an attack of panic."
J.P. Dutta, known for his penchant for epic cinema, has taken on the onus of presenting the life and times of one of the most beautiful women in the world. Says the triumphant director: "It's my good fortune that Gayatri Devi is also in London. I'll be meeting her extensively. The insight she'll offer me into her life would be invaluable. I'll also be depending on her autobiography for facts on her extremely rich and rewarding life."
But will the biopic please the supporters and followers of Gayatri Devi? JP laughs: "I'm aware making biopics in our country is a thankless task. No one is fully pleased. And there's always a controversy accompanying a true-life story.
"But in this case I'm ready to take the risk. To film a life so complete and exemplary would be an honour for any filmmaker. I'm ready for the challenge."