Khan is said to have come up with the idea for a music video featuring all three actors since they do not share screen space as a trio during the film, The Times of India reports.
"Aamir thought something should be done to get all three actors together and be seen together. Hence he came up with the idea of doing a music video where Aamir, Rani and Kareena would be shaking a leg together specially for the film," said a unit-hand.
"Aamir thought the audiences would like to see all three of them together as this trio has never been seen together on the screen ever."
An official spokesperson for the film confirmed the report, saying: "Yes it's true! Aamir came up with the idea of shooting a music video with all three stars together and all instantly agreed. It is a great idea as having Aamir Khan, Rani Mukerji and Kareena Kapoor dancing together in a music video is the recipe for total entertainment."
Talaash is the first big-screen release since 3 Idiots for Khan, who has been concentrating on his TV show Satyamev Jayate.
The film's writer/director Reema Kagti has denied that Talaash is like Kahaani.
Talaash is expected to release on November 30, 2012.