Two judges in the High Court granted him leave to appeal on the basis he could be discriminated against because he is a foreign national.

Counsel for Mr Assange, Edward Fitzgerald, said that the judges should not accept the assurance given by US prosecutors that Mr Assange could rely on the rights and protections under the First Amendment because a US court would not be bound by this.

“We say this is a blatantly inadequate assurance,” he told the court.

Mr Fitzgerald accepted a separate assurance that Mr Assange would not face the death penalty, saying that the US had given an “unambiguous promise not to charge any capital offence”.

Amnesty International called the ruling “a rare piece of positive news for Julian Assange and all defenders of press freedom”.

“The USA’s ongoing attempt to prosecute Assange puts media freedom at risk worldwide. It ridicules the USA’s obligations under international law, and their stated commitment to freedom of expression,” said Simon Crowther, legal adviser at Amnesty.

“It is vital that journalists and whistleblowers are able to participate in critical reporting in the public interest without fear of persecution.”