His supporters are set to gather outside Belmarsh Prison in London, where he is being held as the United States continues its attempt to have him extradited.
The 50-year-old is wanted in the US over an alleged conspiracy to obtain and disclose national defence information following WikiLeaks’ publication of hundreds of thousands of leaked documents relating to the Afghanistan and Iraq wars.
Mr Assange’s fiancee Stella Moris has renewed her call for his release, saying he has spent longer in Belmarsh than many prisoners sentenced for violent crimes.
She said: “His young children, aged two and four, have no memory of their father outside the highest security prison of the UK.
“Julian is simply held at the request of the US government while they continue to abuse the US-UK extradition treaty for political ends.”
Last month, the High Court ruled the extradition could go ahead after the US won an appeal. Amnesty International said it was a “travesty of justice”.
Ms Moris said: “The US government is trying to put an Australian publisher on trial in a US national security court, where he faces a 175-year sentence and imprisonment in conditions of torture and total isolation, simply because he was doing his job.
“Because he received true information about the victims and the crimes committed by US operations in Guantanamo Bay, Afghanistan and Iraq from Chelsea Manning, and he published it.”
She described Mr Assange as a political prisoner and said his “indefinite incarceration” would kill him unless it is brought to an end.
She said: “His lawyers have complained about the limited access they have to their client which has undermined his defence. His requests to attend his own hearings have been refused, and when he has been permitted to attend, his requests to sit next to his lawyers have also been refused.”
WikiLeaks made headlines around the world in 2010 after it published a series of leaks provided by US army intelligence analyst Chelsea Manning.
Mr Assange sought political asylum in the Ecuadorian embassy in London for seven years from 2012. He was facing extradition to Sweden over allegations of sexual assault, which he denied, and the case was later dropped.
On 11 April 2019, Mr Assange was arrested after the Ecuadorian government withdrew his asylum and he was taken into custody by UK police.
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