Long-serving star Trudie Godwin with co-star Todd Carty

The twice-weekly series, set in the fictional Sun Hill Police Station, has become a staple in the ITV schedule since its launch 20 years ago.

It has enjoyed a revival in recent years, with ratings reaching up to eight million.

To reflect its flagship status, ITV has now recommissioned 480 episodes.

"The Bill is a great show for us - it consistently performs well and uses its storylines brilliantly to reflect the diversity of ITV's peak time audience," said ITV's director of programmes, Nick Pickard.

The series, which is made by Talkback Thames, has changed much since its inception, with half-hour dramas which usually saw cases wrapped up by the end of an episode.

Now it uses more of a soap opera format, with continuing storylines, and the police officers' private lives as much the focus as that of the criminals

Its recent 20th anniversary episode, which was a special live show, attracted nearly 10 million viewers.