Michael Schumacher's former manager Willi Weber believes the family of the ailing F1 legend should reveal all the facts about his medical condition.

Weber, who was instrumental in guiding Schumacher throughout his career, from the junior ranks to seven F1 world championships, says the former driver's millions of fans have a right to know the truth.

"For some time now, I've been saying that the Schumacher family is not telling the whole truth," Weber told the German weekly magazine Bunte.

"It's time to pour pure wine for his millions of fans," he added, referring to the fact that almost nothing is known about 48-year-old Schumacher's current health status.

"But I'm biting on granite, because for a long time my advice is no longer heard," Weber said.

Weber said he remained hopeful that one day he will once again hear the voice of his old friend and great champion.

"When I'm home alone and the phone rings, I often feel that it will be Michael saying 'Willi, how's it going?' Hope dies last," said Weber.

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