Ali Abbas Zafar, who is currently basking in the glory of the success of his Salman Khan-starrer 'Sultan', has already begun working on his next film. And this time, sources claim, he is contemplating casting Hollywood legend Sylvester Stallone in the lead.

Speculations of a possible collaboration were fuelled after Ali posted a picture with Stallone on social media on July 14. Says a source, "His next is likely to be an action flick and chances are that Stallone will play the title role. Ali admires the actor and has discussed a few plots for the film during their recent meeting. However, nothing has been finalised as of now."

There was buzz that the director is planning a sequel to Sultan, but he squashed the rumours during a recent press conference. Adds the source, "Ali is working on a script that will focus on Stallone's character. It will be larger-than-life and Salman might be a part of it as well. Once everything falls in place, an official announcement shall be made."

If things go as planned, this will be Stallone's second appearance in Bollywood. He had earlier done a cameo in Akshay Kumar and Kareena Kapoor-starrer Kambakkht Ishq (2009). Ali remained unavailable for comment.