Speaking at the Westminster Media Forum this week, Richards was responding to a challenge from the IPA director-general, Hamish Pringle, that the advertising crackdown on food advertising to children was "an accident waiting to happen".
Richards called the charge a "myth", adding that "if you look at our children's (programming) report ... what it shows very clearly is that the decline in investment or spend by commercial broadcasters in children's programming began seven years ago, not last year. You see it step by step every year for the last seven years, so the idea that this change has been caused by the change in advertising is simply not true."
The report, published in early October, found that while the total hours of children's programming has increased by 500 per cent since 1998, investment by commercial broadcasters has halved over the same period.
Pringle said: "Food advertisers started reducing their adspend in children's programming three or four years ago when it became clear that restrictions were on the agenda."