'Nothing George Russell says will stop us from seeking out lively and innovative programming,' said Andrea Wonfor, Channel 4's controller of entertainment.
John Willis, director of programmes, said: 'The ITV companies should think more about competing with the BBC and the satellite channels, and spend less time worrying about us. What's important is that we don't go outside our remit (to cater for minority interests) which we're clearly not doing.'
Sir George, the official regulator of both ITV and Channel 4, said of the channel: 'Once it gets much above 10 per cent of audience share it starts taking revenue from ITV.' In recent weeks its share has been between 11 and 12 per cent. ITV gets around 40 per cent, but any viewers it loses to Channel 4 cost it advertising revenue. This did not matter before this year because the ITV companies sold advertising on behalf of Channel 4; but now they are in direct competition.
Sir George was reflecting the concern of ITV chiefs. A few weeks ago Andrew Quinn and Marcus Plantin, the two senior men in ITV's central networking system, met Channel 4 executives to express their concern.
The channel's summer schedule, released yesterday, contains programmes to attract both large audiences and minorities. Most popular is likely to be Dinomania from 16 to 18 July, a weekend of programmes about dinosaurs timed to exploit interest in the film Jurassic Park.
At the other end of the ratings scale will be a week of programmes on Bosnia and the Balkans in August, and Derek Jarman's film Blue on 19 September. Blue consists of a featureless blue image on screen for 75 minutes, accompanied by a stereo soundtrack (simultaneously broadcast on Radio 3) containing reflections on living and dying with Aids.
Mr Willis said he would have to consider moving Channel 4 News from its 7pm slot if the ITV companies carry out their plan to shift News at Ten to an earlier hour, probably in the autumn. It is unlikely that Channel 4 News would want to move into the vacated 10 o'clock slot because that is when it likes to begin its popular adult programmes.
The ITV companies confirmed yesterday that they wanted to move towards 'an earlier peak-time, half-hour news and a late evening news'.
In the House of Commons, Peter Mandelson, Labour MP for Hartlepool and the party's former director of communications, tabled an Early Day Motion condemning the move and calling on the ITC and Independent Television News to resist it.
The ITC has no power to stop the news being moved, as long as it stays within the peak viewing hours between 6 and 10.30pm.