High definition offers improved sound and picture quality

It means viewers will be able to see shows like Strictly Come Dancing and Cranford in high definition, which offers improved sound and pictures.

The BBC also announced that the Queen's Christmas message would be broadcast in HD for the first time this year.

But Freeview audiences will have to wait, as there is currently not enough space for an HD channel on the service.

Blockbusters

Hit drama Cranford is one of many shows to be shot in HD

The BBC's HD channel has been running test transmissions on satellite and cable since last year, showing such programmes as Bleak House and Silent Witness.

After the official launch, it will operate initially for at least four hours a day, rising to nine hours - from 1500 to midnight - over the coming years, showcasing programmes from across all of the BBC's stations.

Jana Bennett, director of BBC vision, said the HD would make programmes "even more powerful and outstanding".

Forthcoming programmes include The Tales Of Beatrix Potter With The Royal Ballet, Carmen, Jools Holland's Hootenanny and To The Manor Born.

Films will also be shown in HD, with Hollywood blockbusters Kill Bill and Sin City promised for Christmas.

The BBC's channel is the first free-to-air service in high definition, although Channel 4 plans to broadcast its schedule in the format later this year.