File photo of Julian Assange. Photograph:( Zee News Network )
The group which comprises of 117 professionals from 18 nations wrote an open letter to the Lancet medical journal.
A group of 117 professionals from 18 nations have written an open letter to the Lancet medical journal.
They have warned that Assange is ''in dire state of health due to psychological torture'' and could be "effectively tortured to death in prison".
Watch: Doctors Warning : Julian Assange can 'die' in UK jail
They have asked to put an end to the ''psychological torture and medical neglect''.
"We condemn the torture of Assange. We condemn the denial of his fundamental right to appropriate healthcare," they wrote in the scientific magazine.
"Since doctors first began assessing Mr Assange in the Ecuadorian Embassy in 2015, expert medical opinion and doctors' urgent recommendations have been consistently ignored."
"Our appeals are simple: we are calling upon governments to end the torture of Mr Assange and ensure his access to the best available healthcare, before it is too late," the group of doctors said.
UN special rapporteur on torture Nils Melzer has repeatedly warned that Assange has begun to exhibit signs of psychological torture.
Assange was briefly transferred from prison to a medical facility last year because of his frail health.
The 48-year-old Australian is facing 18 counts in the United States, 17 of them under the Espionage Act that could see him jailed for 175 years.
Washington's extradition request will start being heard next Monday at Woolwich Crown Court. Assange is being held at the neighbouring high-security Belmarsh Prison.