Rupert Murdoch's Fox News Channel threatened to sue the makers of the Simpsons over a spoof news ticker, the show's creator Matt Groening has claimed.

Mr Groening said Fox News raised the unlikely prospect of suing a show broadcast by its sister channel, Fox Entertainment, because it wanted to stop the Simpsons parodying its famously anti-Democratic party agenda.

The alleged row centred on a parody of Fox News' rolling news ticker, which included headlines such as "Do Democrats cause cancer?"

Mr Groening said the news channel backed down because it would have caused Fox to bring a lawsuit against itself.

"Fox said they would sue the show and we called their bluff because we didn't think Rupert Murdoch would pay for Fox to sue itself. We got away with it," Mr Groening told National Public Radio in the US.

"But now Fox has a new rule that we can't do those little fake news crawls [tickers] on the bottom of the screen in a cartoon because it might confuse the viewers into thinking it's real news," he added on NPR's Fresh Air programme.

The episode of the Simpsons in question showed a rolling news ticker at the bottom of the screen, which read: "Pointless news crawls up 37 per cent... Do Democrats cause cancer? Find out at foxnews.com... Rupert Murdoch: Terrific dancer... Dow down 5,000 points... Study: 92 per cent of Democrats are gay... JFK posthumously joins Republican Party... Oil slicks found to keep seals young, supple..."

Fox News denied the channel had ever threatened legal action.

"We are scratching our heads over here. We liked the cartoon. We thought it was great," Robert Zimmerman, a Fox News spokesman, told the Independent.

Last year the makers of the Simpsons apologised to Brazilian tourist officials who had threatened to sue over an episode that poked fun at Rio de Janeiro.

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