"Despite the medical urgency of my appeal, and the seriousness of the alleged violations, the UK has not undertaken any measures of investigation, prevention and redress required under international law," Melzer said. "In my view, this case has never been about Mr. Assange’s guilt or innocence, but about making him pay the price for exposing serious governmental misconduct."
Melzher has previously said that Assange's treatment constitutes torture, noting that the WikiLeaks founder is exhibiting all the symptoms of an abused victim.
In late May, UN Special Rapporteur on torture Nils Melzer released a statement condemning the "deliberate and concerted abuse" inflicted on Assange for years by the governments of the US, the UK and Sweden. He said Assange had been systematically persecuted and his health had deteriorated as a result of his prolonged exposure to stress and psychological trauma.
In September, Assange's lawyer said that the WikiLeaks founder was experiencing serious health problems in detention due to him being isolated for the majority of the day. Soon after, Assange's father also said his son was suffering from anxiety and being subjected to torment in the UK prison.
Assange is currently wanted by the United States on espionage charges over his work with WikiLeaks, which published various classified government documents. On Monday, Assange attended a hearing at a court in London to determine the agenda for future hearings for his potential extradition to the US.