Channel 4 is accusing the BBC -- which is believed to be planning to plough 拢90m a year into the replacement for BBC Choice -- of muscling in on a market that is already served by its own offering E4 and BSkyB's Sky One.
Channel 4, which originally supported the BBC's digital plans, said BBC3 would seriously affect its digital youth channel.
The station said that by the BBC's own research "it will take some of its audience from E4 and its terrestrial service Channel 4".
Channel 4 also hit out at BBC chairman Gavyn Davies' claims that E4 relies too heavily on US imports, such as Friends and ER.
Channel 4 defended its US-heavy programming because "over recent years we have an unrivalled track record in developing innovative British entertainment talent including Graham Norton, Smack the Pony, Ali G, Johnny Vaughan and Dom Joly".
Earlier cable operator NTL also came out in oppostion to BBC3 when it met with the Department of Culture, Media and Sport this week.
NTL told the Commons media select committee it thinks it is unfair that while commercial broadcasters like BSkyB have to pay for carriage over NTL's network, current legislation means that NTL has to carry BBC channels for free.
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