LONDON (AP) — Britain’s High Court is set to rule Friday on whether to overturn an earlier decision and allow WikiLeaks founder Julian Assange to be sent to the United States to face espionage charges.

A lower court judge earlier this year refused an American request to extradite Assange to the U.S. to face spying charges over WikiLeaks’ publication of secret military documents a decade ago. District Judge Vanessa Baraitser denied extradition on health grounds, saying Assange was likely to kill himself if held under harsh U.S. prison conditions.

Appealing against that decision at the High Court in London, an attorney for the U.S. government denied that Assange’s mental health was too fragile to withstand the U.S. judicial system. Lawyer James Lewis said Assange “has no history of serious and enduring mental illness” and does not meet the threshold of being so ill that he cannot resist harming himself.

U.S. authorities have also told British judges that if they agree to extradite Assange, he could serve any U.S. prison sentence he receives in his native Australia.

U.S. prosecutors have indicted Assange on 17 espionage charges and one charge of computer misuse over WikiLeaks’ publication of thousands of leaked military and diplomatic documents. The charges carry a maximum sentence of 175 years in prison, although Lewis said “the longest sentence ever imposed for this offense is 63 months.”

Assange, 50, is currently being held at London’s high-security Belmarsh Prison.

Whichever side loses Friday's decision is likely to appeal.