LONDON (Reuters), -WikiLeaks founder Julian Assange had Monday the opportunity to challenge a decision allowing his extradition to the United States. He will face 18 charges, including one for spying to Britain’s Supreme Court.

U.S. authorities are seeking Australian-born Assange, 50, to face trial on 18 counts relating to WikiLeaks’ release of vast troves of confidential U.S. military records and diplomatic cables which they said had put lives in danger.

The High Court of London in December overturned an earlier court ruling that he shouldn’t be extradited due to his mental illness. He was at high risk for suicide.

Judges denied his request to direct appeal against their decision to the Supreme Court, but they indicated that his case was important and that he could seek the ruling of the United Kingdom’s top court.

The court affirmed that the respondent had been granted leave to appeal and was allowed to certify one point of law. The court denied leave for appeal by the respondent to the supreme Court.

The Supreme Court must decide whether to hear the challenge.