Metallica working on a 3D film

London: American heavy metal band Metallica are working on a self-financed 3D concert film.

The 3D project is at early stage of production, and is expected to release by summer next year.

"There is indeed a 3D project in the very early stages of production! We wish we could tell you more, but we don`t have all the finer points nailed down just yet," quoted the band as saying.

"We tend to pay for these things ourselves. The minute you take somebody else`s money, you have to consider their opinions. And that`s no fun," said drummer Lars Ulric.

The group which also includes vocalist James Hetfield, guitarist Kirk Hammett and bassist Robert Trujillo originally had reservations about making the film.

"We didn`t want to do it at first. We were sold on it by our managers, that it would be a lot of fun and we would have a big-ass stage to play on - the biggest Metallica live show we`ve ever done, next-level stuff," said Hammett.