A British judge ruled on Monday that WikiLeaks founder Julian Assange should not be extradited to the United States to face criminal charges including breaking a spying law, saying his mental health problems meant he would be at risk of suicide.

US authorities accuse Australian-born Assange, 49, of 18 counts relating to the release by WikiLeaks of vast troves of confidential US military records and diplomatic cables which they said had put lives in danger.

His lawyers had argued the entire prosecution was politically motivated, powered by US President Donald Trump, and that Assange’s extradition would pose a severe threat to the work of journalists.

At a hearing at London’s Old Bailey, Judge Vanessa Baraitser rejected nearly all his legal team’s arguments but said she could not approve his extradition as there was a real risk he would commit suicide.

Assange, she said, suffered from at times severe depression and had been diagnosed with Asperger’s syndrome and autism, albeit he was “a high functioning autistic case”.

Half a razor blade was found in his London prison cell in May 2019 and he had told medical staff about his suicidal thoughts.

“I find that Mr. Assange’s risk of committing suicide, if an extradition order were to be made, to be substantial,” Baraitser said in her ruling.

“Faced with conditions of near total isolation ... I am satisfied that the procedures (outlined by US authorities) will not prevent Mr. Assange from finding a way to commit suicide.”

Lawyers for the US authorities are expected to appeal against the decision.

US prosecutors and Western security officials regard Assange, the founder of WikiLeaks, as a reckless and dangerous enemy of the state whose actions put at risk the lives of agents whose names were in the material.

The US authorities say more than 100 people were put at risk by the disclosures and about 50 had received assistance, with some fleeing their home countries with their spouses and families to move to the United States or another safe country.

Supporters regard him as an anti-establishment hero who has been victimised because he exposed US wrongdoing in wars in Afghanistan and Iraq, and say his prosecution is a politically motivated assault on journalism and free speech.

Baraitser rejected this, however, saying there was insufficient evidence that prosecutors had been pressured by Trump’s team and there was little evidence of hostility from the US president towards him.

She said there was no evidence that he would not get a fair trial in the United States or that prosecutors were seeking to punish him, and said his actions had gone beyond investigative journalism.