WikiLeaks founder Julian Assange has received permission to appeal the decision to extradite him to the United States, where he could face life in prison, AFP reported.

Washington wants to put a 50-year-old Australian on trial over the release of 500,000 classified military files relating to the US-led wars in Iraq and Afghanistan.

In December, the London High Court overturned a lower court's decision not to send him to the United States on the grounds that he might commit suicide.

But Assange's lawyers then challenged the decision, arguing that the country's highest court should rule on questions of law of public concern.

Defendant's motion for proof of eligibility is granted, Judges Ian Burnett and Timothy Holroyd said in a written order.

Now the Supreme Court must decide whether to hear the case.