London could get terrestrial HD in 2010

Selected UK regions could get terrestrial HD channels before their analogue signals are switched off, according to detailed new Ofcom plans for changes to the platform.

The regulator said it had "provisionally identified a frequency in London which could be used to extend the coverage of the Multiplex B service to up to 3.3m households up to two years earlier than the currently planned DSO schedule for this region in 2012".

Next month the commercial public service broadcasters will be invited to put forward proposals for new services to be carried on Multiplex B. Two chunks of capacity - each enough for one HD stream - are on offer.

Though the services do not have to include high definition channels, HD content is expected to play a significant part.

Ofcom has set out what it calls a "challenging timetable" for broadcasters to put forward their bids in the "beauty contest". They have to submit their proposals in July or August and Ofcom will decide if and to whom it will award capacity by the end of September.

The regulator has already agreed that BBC HD should be carried on Multiplex B. Previously it was expected that the services would be introduced region-by-region as analogue TV is switched off, starting with Granada at the end of next year.