Telewest acquired Flextech two years ago. The write-down is expected to tip the company into pre-tax losses of £1.8bn, when it announces its full-year results on March 1.
Flextech, Telewest's programming and entertainment division, produces a range of digital channels in conjunction with the BBC, including UK Gold, Play UK and Bravo.
News of the write-down comes amid fears that CEO Adam Singer -- who joined Telewest from Flextech, taking over from former Telewest CEO Tony Illsley -- is struggling to convince investors that Telewest is fully funded.
However, the news did not restore confidence among Telewest investors -- its shares fell 1.92% this morning to 19.75p after staging a small recovery at the beginning of the week to reach 25p yesterday morning.
The shares fell as low as 15p last week, after speculation mounted that it could be merged with UK rival NTL, which is sinking under a debt mountain of £12bn. When Telewest paid for Flextech in January 2000 with shares, they were worth 375p each.
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