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British Judge Vanessa Baraitser has denied bail to WikiLeaks founder Julian Assange after previously rejecting the United States' extradition request.

The judge on Wednesday ruled "there are substantial grounds for believing that if Mr. Assange is released today he would fail to surrender to court and face the appeal proceedings," and so he will remain in prison in London, CNN reports.

Earlier this week, Baraitser denied a request by the U.S. to extradite the WikiLeaks founder, ruling that "the mental condition of Mr. Assange is such that it would be oppressive to extradite him to the United States of America." The Justice Department is appealing the decision.

Assange faces U.S. espionage and hacking charges in connection with WikiLeaks' publication of classified communications. He has been in custody since April 2019 after being arrested for skipping bail, The Associated Press reports.

While Assange's lawyer argued he has "every reason to stay in this jurisdiction where he has the protection of the rule of law and this court's decision" after the United States' extradition request was denied, the judge concluded that "as far as Mr. Assange is concerned this case has not yet been won," and "Mr. Assange still has an incentive to abscond from these as yet unresolved proceedings."