The new production will be directed by the actor-producer's wife Kiran Rao, Mumbai Mirror reports.
"The film will be titled Disco Fighter and Kiran Rao is currently writing it. When Delhi Belly was in the post-production phase, Aamir came up with the idea of making a sequel to the film," a source said.
The original film hints at a possible sequel through the recurring image of the film's poster, with the tag 'Aamir Khan in and as Disco Fighter'.
The level of success that the controversial film has achieved since it came out on Friday is said to have prompted a second instalment.
"Aamir was always of the opinion that if the film works well, a sequel should definitely be made. However, since he is busy with Dhoom 3 right now, he has asked Kiran Rao to take over the project. But the whole idea of how to take the film forward came from Aamir," the source added.
The largely English language comedy has had the second biggest Bollywood opening of 2011 after Salman Khan's Ready.
The 3 Idiots star spoke to Digital Spy earlier this year about Indian cinema audiences moving away from commercial projects.
"I'm glad to see there are more and more audiences for unusual films and more filmmakers coming up also with unusual topics to make films on," he said.
> Read our Imran Khan Delhi Belly interview here