Back in 2006, when Jonathan Ross signed an £18 million deal to tie him to the BBC until 2010, becoming Britain’s highest-paid presenter, he was hailed as irreplaceable.

In the face of uproar as to the sheer size of the deal, the corporation explained that ITV and Channel 4 had each offered him £15 million and they had no choice but to increase their original £12.5 million offer.

When he returns next year to seek to extend the deal, he may be in for a shock. Outside the BBC, insulated by the £3.4 billion it receives via the licence fee, commercial broadcasters are suffering at the hands of a brutal advertising downturn.

ITV has cut 1,000 jobs as revenues have slumped, with Channel 4 making 150 staff redundant. Analysts gave warning that the advertising market could fall by as much as 10 per cent next year as companies cut spending in the face of the credit crunch.

Carol Vorderman, the former co-host of Channel 4’s Countdown, has already felt the pinch, leaving the show after being told that she faced a 90 per cent cut to her reputed £1 million-a-year salary.

Broadcasters will be unable to proffer the riches that they did two years ago. One former senior BBC executive said that he thought Ross would find his salary falling by as much as half.

Other showbiz agents also agreed that Ross may find it harder to land such a huge contract again.

Mark Borkowski, who represents Noel Edmonds, said: “We’ve just passed through the overinflated times. Ross has a huge following and the audiences love him, but with controversy like this the commercial broadcasters don’t want to annoy their advertisers.”

But any decision to try to drop Ross may have unwelcome consequences, Mr Borkowski said. The presenter is represented by Addison Creswell, whose firm, Off The Kerb, also has on its books such in-demand stars as the comedians Jack Dee and Jo Brand. Mr Borkowski said: “Addison Cresswell has a stellar cast of talent that all broadcasters want. When you have a roll call of talent like that in your stable, you have huge bargaining power. Would you want to go into battle with that?”

Ross has said that he has an affinity with the BBC and that he enjoys the fact that he can both appear on television, on his Friday Night With Jonathan Ross show, as well as his Radio 2 Saturday show. Were he to leave the BBC, he could look to follow the lead of Ricky Gervais, who has laid claim to the title of producing the world’s most downloaded podcast, independently of any broadcaster, with an average of 295,000 per episode. After establishing the success of the format, Gervais resolved to charge £4 for four instalments of the programme.

Russell Brand does not enter the same league as Ross when it comes to pay, and is thought to pick up about £200,000 a year for his radio show.

He has carefully cultivated a following in the US, where his foppish image has met with bemusement and celebration in equal measure. Last month, however, he angered many Americans by describing President Bush as a “retarded cowboy” as he hosted the MTV Video Music Awards.

“They are a lot more anxious about these things over in the US,” Mr Borkowski said. “This controversy will pedal across the water.”

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