Veteran Bollywood actor-filmmaker Manoj Kumar is working on his next directorial venture which would be based on Aryabhata, the famous mathematician from the classical age.

"I'm going to return as a director soon. I am working on a film on Aryabhata. It is an interesting story to tell viewers about his contribution," Kumar told PTI. "We have been working on the film for a very long time. Since three years we are working on script, as it is a difficult subject to deal with," the 78-year-old writer -producer said.

Aryabhata was the first of the major mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy.

Manoj Kumar is scouting for newcomers for the film. "We are working with Kishore Namit Kapoor (Indian actor, author and film-acting trainer) who has trained some of the most prominent film actors like Hrithik Roshan, Kareena Kapoor, Priyanka Chopra. He will help us with it (casting)," he said.

Kumar made his official debut as a director with 'Upkar' in 1967 and his last directorial venture was "Jai Hind" in 1999.

Best known for his patriotic films 'Purab Aur Paschim', 'Upkar' and 'Kranti', Manoj Kumar was on Friday chosen for the prestigious Dada Saheb Phalke award, the highest official recognition in Indian cinema.