The Conservative leader's attack on the "bloated BBC" follows the obscene-calls row involving Jonathan Ross, the £6 million-a-year chat-show host, and presenter Russell Brand, who has since quit the corporation.

Fifty BBC executives are paid more than £189,994, the salary of the Prime Minister. Mr Cameron called for the bumper pay deals to be reined in.

"Why on earth is the director-general (Mark Thompson] paid more than £800,000 a year? More than 50 people of this great public institution get more than the Prime Minister," he wrote in an article for The Sun newspaper. "It's become bloated, with many of its executives overpaid."

Mr Cameron, a former boss at rival ITV's Carlton firm, also warned that the BBC could "crush" smaller media and internet companies as it piled into other areas of business. Its plans for online local news video could hit local newspapers, he said.

"The squeezing and crushing of commercial competitors online or in publishing needs to be stopped," he said.

Mr Cameron pointed to the corporation's buy-out of the Lonely Planet travel guides as a questionable acquisition.

Jeremy Hunt, the shadow culture secretary, recently called for an examination of the BBC's impact on competition with its plans to spend £25 million on local websites.

The Tory leader said that the broadcaster should give back any leftover sums from the digital switchover.

"The BBC was given extra money for digital and if that money isn't spent on digital, I think instead of finding new ways to spend it, perhaps that money could be given back to licence-fee payers," he told BBC Radio 4's World at One.

"There are issues of overpayment. There are issues of it piling into areas where sometimes it can crush small businesses starting up on the internet or in education or tourism, where perhaps it shouldn't be going."

Mr Cameron raised the prospect of cutting back the activities of the corporation, which he said "had become oversized and overreached itself".

Meanwhile, Sir Michael Grade, the ITV chief executive, yesterday called for less swearing in British broadcasting in the wake of the BBC phone row.

Sir Michael, who defected from the BBC to ITV in 2006, said that the furore caused by the obscene calls made by Ross and Brand to the 78-year-old actor Andrew Sachs should trigger a debate on taste and decency.

Speaking at a lunch with the Broadcasting Press Guild, Sir Michael said British broadcasters had become too casual in allowing swearing. He said: "I think there is a kind of pattern in the prevalence of bad language and the 'F-word' is a little unrestrained. I don't think we take enough care of the use of the F-word and similar words. It used to be that you would have to get a very, very senior sign-off to use that word in a show."

• Jeremy Clarkson has sparked fresh BBC controversy by joking about murdering prostitutes.

The Top Gear presenter, 48, made the quip about lorry drivers killing sex workers on Sunday night's BBC2 show.

His comments came after Steve Wright, a former lorry driver, was convicted in February of murdering five prostitutes in Ipswich. Clarkson's joke sparked 188 complaints.


WHAT NEXT

MOVES to rein in bumper BBC pay packets may drive the broadcaster's biggest stars away.

The growing public backlash amid a looming recession means the days of £18 million three-year contracts – like that of Jonathan Ross – are coming to a close. There are fears that top presenters such as Graham Norton, Jeremy Paxman and Fiona Bruce could decamp to rivals, including Sky and ITV.

Mark Thompson, the director general of the BBC, will discuss pay with the organisation's executive remuneration committee. On Sunday, Mr Thompson admitted the BBC could secure the best talent "for less than we have been able to do in the last few years".

However, Ross, who left the risqué message on the answer phone of the actor Andrew Sachs, is not alone in securing a generous contract.

Paxman, whose jibes against the "Scottish Raj" have landed him in trouble in Scotland, earns £1 million a year.

Meanwhile, Norton earns £2.5 million a year and newsreader Bruce is on an annual salary of £800,000.