"I had spoken to Aishwarya last year while we were working on 'The Last Legion' and she very generously agreed to do the movie with me," said British actor Ben Kingsley, who is co-producing the film.
"The romance will also include Shah Jehan's abject isolation for years in a prison cell," after the death of his beloved wife giving birth to their 14th child, he told the Times of India.
Kingsley will play the lead role of Emperor Shah Jahan in the movie, which will be shot next year in Agra where the Taj Mahal stands on the banks of the river Yamuna.
Kingsley -- born Krishna Bhanji to a father of Indian extract and an English mother -- is best known on the sub-continent for the Academy-award winning 1982 hit 'Gandhi'.
Emerald-eyed Rai, who played Indian warrior Mira in The Last Legion, is already in the role of a Mughal princess in Bollywood film Jodha Akbar, which is due for release in January 2008.

Copyright AFP (Agence France-Presse), 2007