Ranbir Kapoor says he will try to imbibe qualities and personality of Sanjay Dutt for preparing for the upcoming biopic on the 'Munnabhai' actor.

The biopic on Dutt will be directed by filmmaker Rajkumar Hirani. "When I'll start Rajkumar Hirani's biopic on Sanjay Dutt, I will try to be like him, get his body type... He had put on some weight too... I don't know how much weight I'll put on. When the discussions will begin regarding the film maybe then I'll decide," Ranbir told reporters.

The 'Bombay Velvet' star will be seen doing a biopic for the first time and says physical transformation is very important for an actor. "As an actor, it is our responsibility that when we come on screen people say its something different... It's important to have a physical transformation on screen."

Dutt, 56, is lodged at the Yerwada prison in Pune where he is serving the five-year sentence for possession of illegal arms and ammunition in the 1993 Mumbai serial blasts case.