saying that his fingernails "sometimes fall off" and his teeth are rotting. Lai, 78, has been detained since December 2020 and faces life in prison. This month he was convicted of colluding with foreign forces under the city's controversial national security law (NSL). Hong Kong and Chinese authorities have denied that Lai has been mistreated in prison, saying he is in "good health". The BBC has seen a letter written by Lai's family urging UK Prime Minister Keir Starmer to call for Lai's release when he meets Chinese President Xi Jinping next month. His daughter Claire Lai, who is in exile in London, told the BBC that she fears she "may never see him again". "Of course I worry that my father is going to be a martyr, and I don't want him to be a martyr. But I would not be here today, I would not be speaking out if I didn't think this was his best chance of reuniting with our family."

She described her father as an "extremely robust and strong man" when he went to prison, but said over the last year he has "lost a significant amount of weight".  "He is diabetic, he has heart issues which he never had in the past. He has fingernails that turn purplish grey and sometimes fall off. He has teeth that are rotting."He has back and waist pains. Some days it's painful for him to stand. Sometimes he can't stand. And some days he can't even get out of bed."

Lai's family has, on multiple occasions, flagged concerns about his deteriorating health. Lai's son, Sebastien, told the BBC earlier that his father's "body is breaking down". A spokesperson for the Commissioner's Office of the Chinese Foreign Ministry in Hong Kong stated  this month that Lai's "lawful rights and interests have been fully protected, and he is in good health". They added that "a safe, humane, appropriate, and healthy custodial environment in accordance with the law" has been provided for Lai. (BBC)