The Swedish Supreme Court has rejected WikiLeaks founder Julian Assange's appeal to lift the arrest warrant against him.

Assange still faces arrest if he leaves the Ecuadorian embassy where he has been living in political asylum since 2012. He has said he fears being extradited to the U.S., where an ongoing investigation into WikiLeaks is still underway, if arrested by Swedish authorities. WikiLeaks in 2010 published more than 700,000 classified military and State Department documents, some of which exposed U.S. war crimes.

The arrest warrant stems from sexual assault allegations against Assange in Sweden, although he has not been formally indicted.

"The supreme court notes that investigators have begun efforts to question Julian Assange in London. The supreme court finds no reason to lift the arrest warrant," the court stated on Monday.

Assange has denied the allegations against him. In March, Swedish prosecutors offered to interview him in London, dropping their years-long request that he come to Sweden for questioning. Assange has agreed to be interviewed in London, his lawyer said last month.