Saw this promotional clip that had Ajay Devgan and perhaps Vidya Balan (not sure) that has this catchy tune that goes like this:

??? ??? ????
Kal Ki Soch ---- (or, perhaps it is "Ab Ki Soch")

Any idea which Ajay Devgan film is this song from ??

Thanks.

It's from Halla Bol - the song is Is Pal Ki Soch.

Thanks Bhaskar. It sure is Halla Bol. A tiny portion of clip that I saw, the girl looked like Vidya Balan but I was not sure about it as I saw it for a short few seconds only. Checking film cast & crew, Halla Bol sure has Ajay & Vidya Balan.