Britain would be on stronger ground campaigning against authoritarian regimes if it pressed the Biden administration to drop its call to extradite Julian Assange on espionage charges, Stella Moris, Assange’s partner, has told the Guardian. Moris – who has two children with Assange – is trying to broaden the campaign of support for him by pointing to the global damage caused to the UK’s reputation by keeping him in jail for so long. In an interview coinciding with the second anniversary of his detention in the high-security Belmarsh prison in south-east London, she says: “The treatment of Julian is compromising the UK constantly all round the world. It’s giving authoritarian governments points to score all round the world both privately and in international fora like the UN. You cannot start a new values competition with China with Julian Assange in Belmarsh for publishing war crimes. It just does not work. You don’t get to take the moral high ground with this as your starting point. “Jake Sullivan, the US national security adviser, said the difference between China and the US is that China puts its critics in prison. I am not sure the British government is aware of how much international criticisms it is facing over this issue, or the damage it is doing to its soft power reputation. It’s a tool to whack the UK again and again. It is the perfect response for authoritarian leaders when they are criticised by the UK, or pressed to release political prisoners: ‘What about Julian Assange?’” She said the UK Foreign Office was running a major global press freedom campaign, and yet at the same time keeping Assange in jail. “Every major human rights group – Amnesty International, Human Rights Watch, and Reporters without Borders – are on the same page about this issue.“ Moris portrays Britain as caught by a highly political case launched by the Trump administration as part of its war on journalism – a war that never had much support in the US. So far, the new Biden administration, to the disappointment of Moris, has said it will appeal against the UK court’s decision, made in February, to refuse extradition on the grounds Assange’s mental health meant there was a real risk he would commit suicide in US prisons. The court rejected most of the free press arguments lodged by Assange’s lawyers to reject extradition. It also refused Assange bail. But Moris is hopeful that the new US attorney general, Merrick Garland – who has a strong record on first amendment issues – will look at the Assange case afresh. Moris claims that “it’s seen in the US as a Trump administration prosecution driven by Mike Pompeo. They said they wanted a head on a pike.” The Obama administration, no fans of Assange, chose not to prosecute him, saying it could find nothing that did not amount to newsgathering and if it did charge him it would have to charge other organisations that had published the same material, such as New York Times and the Guardian. Moris claims the pressure is real on the Biden team from civil liberties groups. New supporters pop up all the time. Kylie Moore-Gilbert, herself released from an Iranian jail and according to Moris a cousin of Assange’s, has joined the ranks calling for his release. She says the court was right to be concerned for his wellbeing in a US prison given his mental health history, including the professional medical diagnosis of Asperger syndrome, presented in his case as an obsessiveness and an inability to understand how others might be thinking. Moris says: “The prison system in the US is atrocious. On any given day there are an estimated 80,000 people in solitary confinement. He is a suicide risk, which means they would keep him under constant watch. He is a high-profile national security prisoner so they would keep him away from others.” If the US does press an appeal to secure his extradition, it is likely Assange’s lawyers could go into a cross-appeal on some of the press freedom issues raised but rejected. The consequences for journalism are wide, Moris argues, including for British journalists who report on sensitive information about foreign powers. But the danger for the Assange team is that he is left in limbo, neither released or extradited, as the case drags on. The case has been going on for so long Boris Johnson probably feels little domestic political pressure over the issue – it is not an issue that seems to animate the Labour party under the leadership of a former director of public prosecutions – and if something does happen once every three months to spark media interest, the Home Office can push out a line that has been on file for years. She said she speaks to Assange by phone most days. “We sometimes have to talk about the case but he likes to hear about normal life and the kind of escape that gives him. Prison especially under Covid is all encompassing. You have no power to do anything. There is no agency, no autonomy. It is your entire world, so it is important to get his mind out of there. It is such a fucked up situation. Winning your case does not seem to matter. “Sometimes I have to hide how much of an emotional struggle it is, I have good days and I have bad days, but I feel the trajectory has to be that he is going to be released, and that has to happen soon. But yet he is still in there.”