Actor James Gandolfini has played Tony Soprano since 1999

The show returns in March 2006 after a two-year hiatus. A break will separate the first 12 episodes and the final eight, due to be aired January 2007.

"We are thrilled that [series creator] David Chase felt there are more stories to be told," said HBO's Chris Albrecht.

The sixth season of the hit mob drama was expected to be the last, but there have been hints it will continue.

"When something is as remarkable as The Sopranos, our audience would like to see it continue as long as possible," said Albrecht.

No decision

The channel has pointedly refused to describe the extra eight shows as either a seventh season or "final" episodes.

But the fate of the show rests entirely in Chase's hands. Lead actor James Galdolfini has said he would not continue in the role of Tony Soprano without him.

The Sopranos won four Emmy awards in 2004, including best drama series.