UK communications watchdog Ofcom has promised high-definition television (HDTV) services for free.

The BBC, ITV, Channel 4 and Five have signed a memorandum of understanding to provide HDTV programmes on Freeview in 2009-2012.

Ofcom has stated that this will be possible without allocating additional spectrum to carry more data.

"Today's consultation sets out how this can be achieved without using additional radio spectrum, which is a scarce and valuable resource, while protecting existing services," said the regulator in a statement.

"Ofcom believes that the upgrade could be complete in time for digital switchover in the Granada television region, which is due in late 2009 or early 2010.

"The new services would then be available as the switchover is rolled out across the rest of the UK, completing with four HD services being available by 2012."

Ofcom said that the move could be achieved by upgrading broadcast technology to handle the extra data flow. One of the two Freeview channels set aside for the BBC will be shared with others to ease handling of the load.

The BBC will probably be the first to introduce free HDTV programmes. The corporation has been shooting some media in HDTV for a number of years in anticipation of the change.

Jana Bennett, director of BBC Vision, said: "BBC HD will be available on cable, satellite and, in due course, on digital terrestrial and the internet.

"It will showcase a rich mix of the BBC's programmes from across its channel portfolio in true, native high definition.

"Audiences can look forward to the likes of Earth: Power Of The Planet, Cranford, Torchwood, Hammond's Heroes, Diary Of Anne Frank, Around The World In 80 Gardens and Live at the Apollo in extraordinary sound and vision."