Two judges in London ruled Monday that Assange should be allowed to petition the Supreme Court to consider his case, on the grounds that it raised issues of "general public importance," the UK Press Association reported.
The ruling does not guarantee Assange a hearing. Judges will consider his petition and then decide either to hear the case or reject it.
The chances of success in the Supreme Court were "extraordinarily slim," one of Monday's judges, Sir John Thomas, told Assange.
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This petition is the last possible chance Assange has to fight his extradition, according to his lawyer, Gareth Peirce: she told the BBC that if the Supreme Court turned the petition down, Assange would have exhausted all his legal options in Britain.
Assange's lawyers now have 14 days to lodge a formal appeal. That time-frame makes it likely Assange will remain in the UK into 2012, Reuters said.
Swedish prosecutors want to question Assange over allegations of rape and sexual assault made against him by two former Wikileaks volunteers. He denies the accusations, which he says are politically motivated.
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