Muhammad Ali’s family is locked in a bitter feud over the former heavyweight boxing champion as his life slips away, his brother, Rahman Ali, claimed.

Rahman Ali said his sister-in-law Lonnie has cut off Muhammad Ali from his family and is “draining” him as his mental and physical faculties are eroded by Parkinson’s disease.

Muhammad Ali’s brother lives in poverty in a small flat in his family’s hometown of Louisville, Kentucky, where the boxing legend owns one of his three mansion homes.

Rahman Ali said he and his family had been barred from visiting the three-time heavyweight world champion and could only speak to him on the phone.

“We’ve all been pushed out. The only time I get to see him is at public events,” said Rahman Ali, himself an ex-boxer.

“She and her family are draining him. It’s so sad. There’s nothing I can do, they’ve blocked us all off.”

Rahman Ali, 69, said his 71-year-old brother was so crippled by Parkinson’s, the degenerative brain condition that has afflicted many ex-boxers, he might not survive until the summer.

“My brother can’t speak – he doesn’t recognize me. He’s in a bad way. He’s very sick,” Rahman Ali told a Sunday newspaper.

“It could be months, it could be days.”

Rahman Ali said his sister-in-law Lonnie has cut off Muhammad Ali from his family and is “draining” him as his mental and physical faculties are eroded by Parkinson’s disease

Rahman Ali, who retired from boxing after suffering several strokes, said he last saw his famous brother in July last year at the Sports for Peace Gala in London.

He said that in the days when his brother could still communicate, he had told him he was not in pain, adding: “I’ve achieved everything I’ve ever wanted to accomplish. Don’t cry for me, I’m in no pain.”

Rahman Ali also claims that his brother, estimated to be worth more than $80million, told him he had set up a trust fund for him. But his sister-in-law had “put a stop to it”.

He added that Muhammad Ali’s nine children were also having trouble getting hold of their father.

Rahman Ali said the closest they get is when Lonnie puts him on the phone, although he is only able to breathe down the line.

“If he knew what was happening and where I’m living now, he’d be as mad as hell, so angry,” Rahman Ali said.

“If he saw what was happening with his children, he’d go crazy.”

The two brothers – born Cassius and Rudolph Clay – were the only two children of poor parents, who worked as a billboard painter and a household domestic.

Rahman Ali copied his brother when he changed his name, but his career in boxing was short-lived and he retired in the 1960s.

Muhammad Ali has been married four times. Yolanda “Lonnie” Williams, became wife number four in Louisville in 1986.