The BBC will trial broadcasts of high definition television in 2006, it announced today.
In the limited technical trials, it is planned to simulcast highlights of BBC ONE's peaktime schedule in high definition on satellite and cable, as available, from mid-2006.
The BBC is in talks with the relevant operators about these plans.
The BBC is also seeking to run a technical terrestrial trial in the London area at the same time. This would not affect reception of existing Freeview channels.
The BBC is considering collaboration with other broadcasters on the terrestrial trial.
The purpose of the trials is to test delivery and reception of high definition broadcasts on the major television platforms.
Director of Television, Jana Bennett, will set out the BBC's vision for future free-to-air high definition television when she takes part in an industry event in London tonight.
She said: "From colour and widescreen to digital radio and television, the BBC has always been at the forefront of innovations in broadcasting. Our promise to our licence payers is to give them the highest quality television, so the time is right for the BBC to get involved in high definition.
"High definition may take time to grow in Britain, but as with the other technologies we helped to build, the BBC wants to prepare now to be able to deliver the benefits of HD to all its licence payers in the long term."
Jana has appointed Seetha Kumar as Head of HDTV for the BBC, to run and manage the trial.
The BBC trial will start on each platform once they become technically viable, and it is expected that these trials will last for about a year. There will be no impact on any current standard service.
Notes to Editors
High definition (HD or HDTV) is a different standard of digital television broadcast which offers sharper, more detailed pictures.
It requires an entirely separate broadcast stream from current standard definition (SD) broadcasting.
Only viewers with an "HD Ready" television set, a special HD set top box receiver and reception of a high definition service will experience true HD programming.
High definition programmes must also be specially shot. Some BBC programmes, such as Planet Earth and Bleak House, are already made in high definition and the BBC has a target to move all production to high definition by 2010.
The BBC HD trial will enable the BBC to test the end-to-end HD production and distribution chain, from capture and post, to playout and coding, to transmission, reception and viewer experience.
Sky has announced plans to launch a commercial HD service to subscribers next year and cable companies are also forming plans.
For the terrestrial trial, the BBC will apply to Ofcom for temporary use of an unused frequency currently not allocated to broadcasters and unsuitable for conventional broadcast use.
It is hoped it will be possible to provide a limited number of HD set top box receivers to triallists.
However, it is unlikely that HD receivers will be available commercially until a long-term future is secured for high definition terrestrial broadcasting.
Capacity for high definition broadcasts on terrestrial television (Freeview) will be very limited until digital switchover - between 2008 and 2012.
Switchover will free some extra spectrum as analogue services are switched off. Ofcom is to decide how this freed spectrum is to be used.
The BBC would like to see some frequencies made available to broadcasters for high definition broadcasting and is working with other broadcasters, Ofcom and the Government to explore this possibility.
HD downloads are part of the BBC's iMP (integrated media player) trial and should soon be available to selected cable subscribers.
Current broadband infrastructure does not enable live HDTV to be offered.
Seetha Kumar was responsible for the ambitious and successful cross-channel, cross-genre and cross-platform seasons, Africa Lives on the BBC and Hitting Home. She also commissioned Body Hits, Make Me Honest, Diet Trials and Your Life in Their Hands.