London, Dec 21: Michael Jackson is reportedly fighting for his life, according to a writer who is penning a new biography on the singer.

Ian Halperin, a former award-winning investigative journalist on America''s respected Rolling Stone Magazine, has said that the singer is suffering from a rare lung condition and needs to undergo an emergency transplant operation, reports the Daily Express.

However, the ailing star is too weak to be rushed into surgery and may even be fighting for his life, claims the writer.

According to Halperin, the 50-year-old has been diagnosed with Alpha 1-antitrypsin deficiency, a genetic condition that can be fatal in severe cases.

And he claims the singer is now so ill he can barely speak and has lost as much as 95 per cent of the vision in his left eye.

Jackson was photographed in Los Angeles ten days ago visiting a doctor prior to shopping in several of his favourite stores with aides. The singer, who wore a Long Ranger style mask and Indiana Jones fedora to almost completely hide his face, was able to walk unaided, despite being seen in a wheelchair earlier this year near his home in Las Vegas.

The writer added: "He has had Alpha 1-antitrypsin deficiency for years but it''s gotten worse. He needs a lung transplant but may be too weak to go through with it. He also has emphysema and chronic gastrointestinal bleeding, which his doctors have had a lot of trouble stopping. It''s the bleeding that''s the most problematic part. It could kill him."

Although Jackson''s official spokeswoman would did not comment on Halperin''s claims, Jackson''s older brother Jermaine seemed to confirm that the singer has serious health issues.

He told America''s Fox TV news: "He''s not doing so well right now. This isn''t a good time." (ANI)