Broadcaster, writer and journalist Clive James has admitted he is "getting near the end", two years after being diagnosed with cancer.

The Australian star, best known for his ITV show Clive James on Television, but also a prolific novelist, poet and cultural critic and commentator, was diagnosed with leukaemia, kidney failure and lung disease in 2010.

James told BBC Radio 4's Meeting Myself Coming Back: "I'm getting near the end. I don't want to cast a gloom, an air of doom, over the programme but I'm a man who is approaching his terminus."

In the show, to be broadcast on Saturday, James said he has "been really ill for two-and-a-half years" and "almost died four times in that period".

However, following the release of material from the Radio 4 programme, James's spokeswoman said the interview had "sounded much less doom-laden than it does when transcribed".

"Clive is in fact in reasonable shape and is looking forward to years of working, writing his books and his column for the [Daily] Telegraph," she added.

James was born in Sydney and came to England in 1961, where he made a career in journalism including a successful stint as a prominent literary critic and TV reviewer for the Observer for 10 years from 1972.

Clive James on Television ran for years on ITV and his wry commentary on TV programmes from around the world, including the Japanese gameshow Endurance, made him a household name.

During a successful TV career in the 1980s and 1990s James also presented travel programmes for ITV and the BBC, various entertainment shows, and the documentary series Fame in the 20th Century.

The father of two, who is married to academic Prue Shaw, said he was facing the fact he might never see Sydney again.

He said: "I've been so sick since January 2010, especially my lung disease, that I'm not allowed to fly. You couldn't get enough oxygen aboard a plane for me to get me to Sydney."

James also spoke about the "defining event" of his life – the death of his father who survived a second world war prison camp only to die on the journey back to Australia. He said: "I never saw him. I think I was in his arms as a baby for one day before he sailed away."

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