Paul Newman has cancer, his longtime neighbour and business partner confirmed last night.

A.E. Hotchner, who co-founded Newman's Own salad dressing in the 1980s, said the actor has been fighting the disease for at least 18 months.

Speculation has been rife that 83-year-old Newman, a former chain smoker, has lung cancer after he appeared gaunt and frail in photographs.

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'He's battling,' said Mr Hotchner, 87. 'He's doing all the right stuff. Paul is a fighter. 'He seems to be going through a good period.'

The novelist and playwright, who lives close to Newman and his wife Joanne in Westport, Connecticut, did not say what form of cancer he has, but said he is undergoing treatment.

Asked about the prognosis, Hotchner said, 'Everybody is hopeful. That's all we know.'

Hollywood icon: Mr Newman shooting pool in a scene from The Hustler

In a statement yesterday, Newman said he is 'doing nicely' but did not specifically address questions about cancer.

Unconfirmed reports say he is receiving treatment for lung cancer at a hospital in New York.

His friend James Naughton, who spoke to Newman on Monday night, said the actor is 'doing very well'.

Michael Brockman, Newman's racing team partner, said Newman 'looked great' when he saw him last weekend.