The fiancee of WikiLeaks founder Julian Assange has hailed his “victory” in his fight to avoid extradition to the United States.

However, Stella Moris said she and the couple’s two young sons cannot celebrate until the day he goes home.

District Judge Vanessa Baraitser said at the Old Bailey on Monday that, due to the real risk of suicide, Assange, 49, should not be extradited by “reason of mental health”.

But his supporters raised concerns that her judgment focused on his health and rejected defence arguments over freedom of speech.

The US government has given notice that it will appeal against the decision and has two weeks to lodge grounds, while Assange has been remanded in custody at high-security Belmarsh Prison ahead of a bail application on Wednesday.

Assange wiped his brow in the dock after the decision was announced, while Ms Moris wept in court before speaking to cheering supporters and journalists outside.

She said: “I had hoped today would be the day Julian would come home. Today is not that day, but that day will come soon.

“As long as Julian has to endure suffering in isolation as an unconvicted prisoner at Belmarsh Prison, as long as our children continue to be robbed of their father’s love and affection, we cannot celebrate.

“We will celebrate the day he comes home.

“Today is a victory for Julian. Today’s victory is the first stop towards justice in this case.”

Assange has been held in Belmarsh since he was carried out of the Ecuadorian embassy in London by police before being arrested for breaching his bail conditions in April 2019.

He had entered the building in 2012 after exhausting all legal avenues to avoid extradition to Sweden to face sex offence allegations, which he has always denied and were eventually dropped.

Assange is wanted in the US to face an 18-count indictment, alleging a plot to hack computers and a conspiracy to obtain and disclose national defence information.

The prosecution followed WikiLeaks’ publication of hundreds of thousands of leaked documents in 2010 and 2011 relating to the Afghanistan and Iraq wars, as well as diplomatic cables.

Prosecutors say Assange helped US defence analyst Chelsea Manning breach the Espionage Act in unlawfully obtaining material, was complicit in hacking by others, and published classified information that put the lives of US informants in danger.

Assange denies plotting with Manning to crack an encrypted password on US Department of Defence computers and says there is no evidence that anyone’s safety was put at risk.

His lawyers had said he faced up to 175 years in jail if convicted, although the US government said the sentence was more likely to be between four and six years.

The defence legal team argued that the US prosecution is political and said Assange, who has been diagnosed with Asperger’s syndrome and severe depression, is a high suicide risk if he is extradited.

Assange, who sat in the dock of Court 2 in a blue suit and wearing a green face mask below his nose, closed his eyes repeatedly as the judge read out her ruling, rejecting a string of defence arguments, including freedom of speech and that the prosecution was politically motivated.

She said: “If the allegations are proved then the agreement with Ms Manning and other groups of computer hackers took him outside any role of investigative journalism.

“He was acting to further the overall objective of WikiLeaks to obtain protected information by hacking, if necessary.”

The judge said Assange’s dealings with Manning “went beyond the mere encouragement of a journalist” and that he was “well aware” of the danger to informants by disclosing unredacted names in leaked documents.

But turning to his mental health, she said: “Notwithstanding the strong and constant support he received from his family and friends, Mr Assange has remained either severely or moderately clinically depressed throughout his detention at HMP Belmarsh.”

She said there was a real risk he would be submitted to Special Administrative Measures and detained at the ADX Florence Supermax jail if extradited.

“I’m satisfied that Mr Assange has the intellect and determination to circumvent suicide prevention measures,” the judge said in her ruling.

“Faced with the conditions of near total isolation without the protective factors which limited his risk at HMP Belmarsh, I am satisfied the procedures described by the US will not prevent Mr Assange from finding a way to commit suicide, and for this reason I have decided extradition would be oppressive by reason of mental health and I order his discharge.”

Speaking outside the Old Bailey, WikiLeaks editor-in-chief Kristinn Hrafnsson said: “I am concerned that instantly, upon giving her decision, the lawyers for the US government indicated they would appeal (against) the decision. They should not.

“And there should be a call out and pressure on the US side to drop the appeal, to say enough is enough.”