"He has already shot for his portions before he went (to jail)," Hirani said at an event on Tuesday. (Agencies)
Dutt went to prison in May last year.
There was a talk in Bollywood circles that the film's release has been pushed to December as Aamir Khan, who features in 'P.K' and is also one of its producers, is busy with his TV talk show `Satyamev Jayate' whose second edition went on air last Sunday.
Also, Aamir had earlier said Hirani wanted to spend more time on the film's editing which is why the release was pushed to December from June 6.
But Hirani cleared the air and insisted the reason for putting off 'P.K' release was because people tend to watch more films during the festive season.
"There is no particular reason for the delay in release. We wanted to release the film in June. But then Christmas seemed apt time. It is festive time and more people tend to watch films during this (festive) period. Also, most of Aamir's films hit the theatres during Christmas and they have done well," the national award winning director said.
The Hirani-helmed political satire also stars Anushka Sharma and Sushant Singh Rajput, besides Dutt and Aamir.
Aamir has had successful Christmas releases—from `Ghajini', `3 Idiots' to last year's `Dhoom 3'.
"He has already shot for his portions before he went (to jail)," Hirani said at an event on Tuesday.