Akshay Kumar has unveiled a surprise big film called Prithviraj on his birthday. The actor, who says this will be one of his biggest films, will essay the role of the 12th century Indian monarch Prithviraj Chauhan in the historical movie. Yash Raj Films will bankroll the project, while Chandraprakash Dwivedi, best known for 90s’ historical TV series Chanakya and 2003 film Pinjar, will helm it. Prithviraj Chauhan ruled present-day Rajasthan, Haryana, Delhi and some parts of Madhya Pradesh and Uttar Pradesh. Akshay took to Twitter to make the announcement.