Really great television has to do more than... just bring in the numbers

David Liddiment

And he singled out BBC One for criticism for failing to lead by example.

But Mark Thompson, director of television at the BBC, said he did not recognise the picture painted of BBC One.

"It was partial and he either ignored or dismissed all of the many programmes that would have disproved his argument," he said.

"We don't believe BBC One is perfect - that's why we are investing heavily in high quality UK programmes for the future - across all genres, including those like science, arts and current affairs that rarely find a place in ITV1's peaktime schedule."

Mr Liddiment stressed he was expressing his personal opinions, not those of ITV.

Mr Liddiment also hit out at the BBC's board of governors, for lack of accountability.

"A small group of lay people have what amounts to sovereign power over the most important cultural institution and biggest creative powerhouse in Britain," he said.

"Do I trust them to do the job? No. Nothing personal, but this is not the way to run a 21st century public body with huge cultural obligations as well as significant commercial interests."

The lack of any kind of coherent vision for ITV was a stark omission from David's remarks

Mark Thompson BBC director of television

But a BBC spokeswoman said: "The governors are clearly accountable to Parliament and to the public.

"They are the representatives of the public and the system of regulation is far more onerous because of the funding, more onerous than any other broadcaster."

Mr Liddiment said all broadcasters faced the same commercial pressures which risked making television a "homogeneous, more driven, less interesting place".

Shows which proved popular predictably led to copycat programmes which he said resulted in "overkill".

"Really great television has to do more than just give people what they want," he said. "More than just bring in the numbers."

Referring to BBC success stories like Walking With Dinosaurs and A History Of Britain, he said: "These begin to look like fig leaves preserving the decency of a nakedly commercial beast."

He conceded that critics would question the comments, coming from ITV, but he highlighted dramas like a modern-day version of Othello and the Yorkshire Ripper drama, This Is Personal.

But Mr Thompson said he was disappointed that Mr Liddiment's speech did not say more about ITV.

"The lack of any kind of coherent vision for ITV was a stark omission from David's remarks.

"ITV is a vital part of a vibrant UK television ecology and so it would have been much more interesting to hear that than a familiar headline-grabbing attack on the BBC.