The service is now available to over 4.5 million homes, Telewest claims, and is accessible via the firm's newly launched TVDrive personal video recorder.
HD programmes will be offered via Telewest's Teleport TV-on-demand service, and delivers four times as many pixels as standard TV broadcasts allowing for crystal-clear pictures.
TVDrive enables viewers to pause and resume live TV using the integrated hard drive which can hold around 80 hours of content. Three onboard tuners mean that two channels can be recorded while watching a third.
TVDrive costs £10 per month for customers taking the company's top digital TV package, or £15 per month otherwise.
At present, consumers can watch free HD programmes from BBC Worldwide, and pay-per-view movies are expected soon.
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