US broadcaster CNN has confirmed that the former Daily Mirror editor, Piers Morgan, will take over from long-serving chatshow host Larry King from January.

Morgan's as yet unnamed live show will take over in King's high-profile daily slot on the cable news channel and will be broadcast in more than 200 countries. Morgan will be based in New York but also work from Los Angeles and London, according to CNN.

"I have watched Larry King Live for much of the last 25 years, and dreamed of one day filling the legendary suspenders of the man I consider to be the greatest TV interviewer of them all," Morgan said.

Jon Klein, CNN US president, added: "Piers has made his name posing tough questions to public figures, holding them accountable for their words and deeds. He is able to look at all aspects of the news with style and humour with an occasional good laugh in the process."

King announced in June that he would be stepping down from Larry King Live, which he has presented on CNN since 1985, bringing down the curtain on a broadcasting career spanning more than 50 years and, by his reckoning, more than 50,000 interviews.

It was widely reported the following month that Morgan, best known to US viewers as a judge on NBC's America's Got Talent, would replace King. However, confirmation of Morgan's CNN deal is understood to have been delayed while is US visa was sorted out.

Talks were also complicated by Morgan's commitments to NBC. His NBC contract prevented him from taking on extra work that clashed with the show, but this has now reportedly been resolved.

Many of the interviews for the CNN show, broadcast in the key 9pm slot on the US east coast, are recorded and Morgan will still have time to star in the NBC talent contest.

Morgan is expected to quit his judging role on Britain's Got Talent as a result of his CNN commitments. But he will continue to make one-off shows for ITV as well as two further series of the interview show Piers Morgan's Life Stories, each running to 12 programmes.

Landing the CNN job caps a remarkable comeback for Morgan, 45, who was sacked as Daily Mirror editor in 2004 for running fake pictures of British troops "abusing" Iraqi prisoners.

He began his rehabilitation with the publication of The Insider, his memoir of a decade mixing with celebrities and politicians as editor of the News of the World and then the Daily Mirror.

Morgan then moved into TV as a judge on Britain's Got Talent, before landing the same role in the US version of Simon Cowell's talent show format and his own ITV chatshow, Piers Morgan's Life Stories.

In June he interrupted negotations with CNN to celebrate his second marriage, to Daily Telegraph journalist Celia Walden.

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