"Mary Kom" director Omung Kumar says convincing Aishwarya Rai Bachchan to do his biopic on Sarabjit Singh was not at all difficult, and she agreed in just 15 minutes.

"We directly approached Aishwarya as I know her since a long time. After meeting her, she agreed to do the film in just 15 minutes as the role was demanding and she could see herself in the role. So she instantly said yes," Omung Kumar said on the sidelines of Smita Thackeray's birthday celebrations.

Sarabjit Singh, an Indian farmer who was convicted of terrorism and spying in Pakistan, was sentenced to death. He was attacked by inmates at a prison in Lahore in April 2013, and died a few days later.

The biopic is from the point of view of Sarabjit's sister Dalbir Kaur, to be played by Aishwarya Rai Bachchan, who endured severe hardship in trying to get her brother released. The title role will be played by Randeep Hooda.

Omung Kumar confirmed that the cast was final.

"Everyone already knows about the actors and they're final. The script is complete, location hunting is currently on and we're looking for a November-December-January shoot for the film. The workshop is scheduled for next month."

Omung Kumar's debut film "Mary Kom" had won the national award for best popular film providing wholesome entertainment.