FILE - In this file photo dated Wednesday May 1, 2019, buildings are reflected in the window as WikiLeaks founder Julian Assange is taken from court, where he appeared on charges of jumping British bail seven years ago, in London. 47-year old Assange is expected to appear via a video link at court Friday June 14, 2019, as he continues his fight against extradition to the United States, where he faces prosecution under the Espionage Act. (AP Photo/Matt Dunham, FILE) Associated Press

Julian Assange is so unwell he could die in prison, a group of 60 doctors have said in a letter to UK authorities.

Assange has been kept at Belmarsh Prison since May 2019 after he was found guilty of skipping bail, which got him a 50-week sentence.

„We have real concerns, on the evidence currently available, that Mr Assange could die in prison. The medical situation is thereby urgent. There is no time to lose,“ according to a letter sent to UK Home Secretary Priti Patel.

Assange’s lawyers, WikiLeaks, and his family have said on numerous occasions that Assange is in dire physical and mental health.

A UK government spokeswoman said that the allegations of ill-treatment are „unfounded and wholly false.“

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Julian Assange is in such poor health he could die in prison, a consortium of 60 doctors said in a joint letter to the UK government.

Assange has been detained inside the UK’s Belmarsh Prison since May. The 48-year-old was in April sentenced to 50 weeks in prison for breaching the Bail Act when he spent years hiding from police in Ecuador’s London embassy.

The letter says: „We write this open letter, as medical doctors, to express our serious concerns about the physical and mental health of Julian Assange.“ It is addressed to Priti Patel, the UK’s Home Secretary.

„Mr Assange requires urgent expert medical assessment of both his physical and psychological state of health.“

Julian Assange supporters gather outside Westminster Magistrates Court in London, Thursday May 30, 2019. Assange has missed a court session apparently due to health problems. Assange had been expected to appear from prison via video link at a brief extradition hearing Thursday at Westminster Magistrates\' Court. (Thomas Hornall/PA via AP) Associated Press

„We have real concerns, on the evidence currently available, that Mr Assange could die in prison. The medical situation is thereby urgent. There is no time to lose.“

In an emailed statement, the UK government dismissed the claim that Assange is being held in dangerous conditions.

It said: „The allegations Mr Assange was subjected to torture are unfounded and wholly false. The UK is committed to upholding the rule of law, and ensuring that no one is ever above it.“

According to official statistics, deaths in UK prisons from ill-health are relatively rare. Excluding self-inflicted deaths, around 2.7 prisoners per 1,000 died in the 12 months to June 2019.

The signatories to the letter are doctors from the US, Australia, UK, Sweden, Italy, Germany, Sri Lanka, and Poland, according to the Guardian.

The letter does not detail Assange’s symptoms. His lawyers, WikiLeaks, and his family have previously cited anxiety, depression, weight loss, and extreme stress.

The UN special rapporteur on torture, Nils Melzer, visited Assange in prison in May said that he has suffered „a downward spiral of progressively severe anxiety, stress and helplessness.“

Assange was due to appear at Westminster Magistrates Court via video link in May, but his lawyers said he was too unwell to attend.

Also in May, Assange was moved to the hospital wing at Belmarsh Prison following a „dramatic“ loss of weight, his lawyers said.

Belmarsh prison london REUTERS/Russell Boyce RUS/PS

Those lawyers are currently battling a request from the US to extradite the WikiLeaks founder so he can be tried over an 18-count indictment alleging espionage and computer misuse crimes.

If found guilty on all counts, he could be sentenced to as many as 175 years in jail.

His extradition hearing is set for February 2020. In their letter, the 60 doctors said they „have serious concerns about Mr Assange’s fitness to stand trial in February 2020.“

Assange had also faced allegations of rape in Sweden, but prosecutors said on Tuesday that they will formally drop their investigation into the allegations.

Two doctors who assessed Assange’s health for 20 hours in January 2018 while he lived in the Ecuadorian Embassy in London said „his continued confinement is dangerous physically and mentally to him.“