Thottumkal turned down the project despite it starring Shah Rukh Khan, who she has previously expressed a desire to work with.
A source told The Times of India: "Ever since Asin appeared on Farah's show Tere Mere Beach Mein, they have been in touch. When Farah offered her the role, initially Asin was quite excited.
"She [later] conveyed that the dates which Farah needed would be clashing with her other assignments."
The 23-year-old actress will next be seen opposite Salman Khan in London Dreams, which is scheduled for release on October 30.