JULIAN Assange's future hinges on the movements of the British justice system, with the WikiLeaks founder imprisoned in London but still wanted on espionage charges in the US.

An early hearing of the American authorities’ bid to extradite him was heard in the High Court today. Here, we look at some of the key questions around the case.

Why does Washington want Assange extradited to the US?

Assange faces an 18-count indictment, alleging a plot to hack computers and a conspiracy to obtain and disclose national defence information.

It was prompted by the publication of hundreds of thousands of leaked documents in 2010 and 2011 relating to the Afghanistan and Iraq wars, as well as diplomatic cables.

The charges allege that Assange conspired with US defence analyst Chelsea Manning to unlawfully obtain classified material. It was also claimed that he published unredacted classified information that put the lives of US sources at risk.

What have his defence argued?

Assange’s team have claimed the publication of classified documents exposed US wrongdoing and were in the public interest.

The WikiLeaks founder denied informants were put in harm’s way or that he plotted hacking with his source Manning.

His legal team claimed the prosecution was politically motivated and also argued that Assange faced up to 175 years in jail, under a torturous regime.

What other concerns do they have?

The defence suggested Assange would be held in segregation under Special Administrative Measures at a supermax jail, conditions usually reserved for convicted terrorists.

The Old Bailey heard evidence Assange is on the autistic spectrum, has suffered from severe depression and would be a serious suicide risk.

Why has he not been extradited?

Following a multi-week hearing last year, District Judge Vanessa Baraitser said the court trusted the US would protect Assange’s right to free speech and noted his dealings with Manning “went beyond the mere encouragement of a journalist”.

But she ultimately rejected the request to extradite Assange on the basis of his mental health alone, siding with the defence’s argument that he was a serious risk of suicide in US custody.

Judge Baraitser refused to release Assange while US prosecutors appeal against the decision over fears he would abscond.

What is the basis of the US appeal?

The US government has been allowed to appeal against the district judge’s decision on some of its grounds, which Assange’s legal team previously described as “narrow” and “technical”.

In the full appeal, which is likely to take place later this year, the US will argue that Judge Baraitser’s decision was wrong in law and she should have also notified the US of her provisional view before making the ruling to address her concerns.

Today, US authorities asked the High Court to allow them to expand the basis that can be used to appeal against the decision not to extradite the 50-year-old.

They said the US should be allowed to argue that the district judge was wrong in how she assessed Assange’s risk of suicide, including the use of evidence from a psychiatrist who allegedly “misled” the court.

What role did Donald Trump play in the current situation?

Assange’s supporters had hoped Donald Trump would pardon the WikiLeaks founder.

The American pardoned or commuted the sentences of 143 people in his final hours in office.

But Assange was not among those on the list, despite calls from his partner Stella Moris for the US Justice Department to drop his charges and the president to offer him a pardon.

Where is Assange now?

Assange remains in south London’s HMP Belmarsh, where he has been since being carried out of the Ecuadorian embassy in 2019, pending the outcome of an appeal.