Earlier news of Deepika Padukone's walkout of "Race 2", hit the tabloids and now Kareena Kapoor, too has decided to opt out of Ekta Kapoor and Milan Luthria's "Once Upon A Time In Mumbai Part 2". It was widely rumoured that Kareena was unsure about taking on the project  due to the possible inclusion of Shahid Kapoor as the second male lead,  as per inside sources.

According to a source close to the actress, it wasn't the second male lead but, she could not allot any more dates to a new project.

"Kareena, who had already committed to the Balaji production was not very happy with the way things were going," revealed the source and added, "All she knew was that she was to play Mandakini's role in the film. The second actor had still not been finalised and Kareena's dates were also not fixed. Around a couple of weeks back, Kareena asked the producers, Balaji, to get back to her with all the details including exact shoot dates, the second lead actor and the final script. Balaji failed to do that. As a result, Kareena has opted out of the project."

Even while Balaji kept her waiting, Kareena was offered another major project in the interim. "It is a big film by a celebrated filmmaker, whose last film had two a-list actors in unconventional roles. Kareena who is already working on 2 big bugdet films this year, Kareena decided to quit "Once Upon A Time"…," added the source.

There is also the buzz about Kareena's upcoming nuptials that prompted her to walk out of the Balaji film. "Saif Ali Khan had announced that the wedding may take place after the release of "Agent Vinod". With her wedding round the corner, Kareena of course did not want any distractions. And she is already working on Madhur Bhandarkar's "Heroine". The wedding might take place around the end of 2012," said the source.