After a years-long legal saga, Wikileaks says that founder Julian Assange has left the UK after reaching a deal with US authorities that will see him plead guilty to criminal charges and go free.

Mr Assange, 52, was charged with conspiracy to obtain and disclose national defence information.

For years, the US has argued that the Wikileaks files – which disclosed information about the Iraq and Afghanistan wars – endangered lives.

For the last five years, he has fought extradition to the US from a British prison.

Mr Assange also faced separate charges of rape and sexual assault in Sweden, which he denied.

He spent seven years hiding in Ecuador’s London embassy, claiming the Swedish case would lead him to be sent to the US.

Swedish authorities dropped the case in 2019 and said that too much time had passed since the original complaint, but UK authorities later took him into custody. He was tried for not surrendering to the courts to be extradited to Sweden.

According to CBS, the BBC’s US partner, Mr Assange will spend no time in US custody and will receive credit for the time spent incarcerated in the UK.

Assange will return to Australia, according to a letter from the justice department.

On X, the platform formerly known as Twitter, Wikileaks said that Mr Assange left Belmarsh prison on Monday after 1,901 days in a small cell.

He was then “released at Stansted airport during the afternoon, where he boarded a plane and departed the UK” to return to Australia, the statement added.

Video shared online by Wikileaks appear to show Mr Assange, dressed in jeans and a blue shirt, being driven to Stansted before boarding an aircraft.

• Julian Assange: A timeline of Wikileaks founder’s case

The BBC has been unable to independently verify the video.

His wife, Stella Assange, posted on X thanking his supporters “who have all mobilised for years and years to make this come true”.

She later told the BBC’s Today programme that the days running up to the US deal had been “touch-and-go” and “non-stop”, and that she was feeling “a whirlwind of emotions”.

The deal – which will see him plead guilty to one charge of the Espionage Act – is expected to be finalised in a court in the Northern Mariana Islands on Wednesday, 26 June.

The remote Pacific islands, a US commonwealth, are much closer to Australia than US federal courts in Hawaii or the continental US.

Stella said she was very limited in what she could say about the deal ahead of her husband’s court appearance. “I don’t want to jeopardise anything”, she said.

“The important thing here is that the deal involved time served – that if he signed it, he would be able to walk free. He will be a free man once it has been signed off by a judge.”

She said the priority for her husband is to “get healthy again”, be in touch with nature, and for the family to have “time and privacy”.

Stella also confirmed that the couple’s two children are in Australia with her, but she has not yet told them that he is to be freed, only that they were going to visit family and that there was “a big surprise” waiting for them.

“We’ve been very careful because obviously no one can stop a five and a seven-year-old from, you know, shouting it from the rooftops at any given moment,” she said.

She later told the BBC’s Newshour programme: “We haven’t had much time to talk about the future – the first thing is that he will have to pay the Australian government $500,000 (£393,715) back for the chartered flights.”

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