Bollywood Mega Star Amitabh Bachchan turned down the invitation from Queen Elizabeth II to participate in a cultural event taking place in Buckingham Palace. Big B declined the invitation for the India Cultural Year reception function owing to professional commitments. Amitabh Bachchan has a tight and packed pre-scheduled commitments' ahead of him. Reports said that Big B has to launch the trailer of his upcoming movie 'Sarkar 3'. Apart from this, Amitabh Bachchan will also be shooting for Vijay Krishna Acharya’s ‘Thugs of Hindostan’ with Aamir Khan and Gaurang Doshi’s ‘Aankhen 2’.