Brisbane, Australia - US Secretary of State Antony Blinken on Saturday defended his country's ongoing efforts to prosecute Wikileaks founder Julian Assange.

At a press conference with his Australian counterpart Penny Wong in Brisbane, Blinken echoed Washington's position on the issue.

"The actions that he is alleged to have committed risked very serious harm to our national security to the benefit of our adversaries and put named human sources at grave risk," Blinken said.

The United States has been trying to secure the extradition of the Australian-born British national for years in a legal tug-of-war. However, Assange's legal options to fight this have now been largely exhausted.

Crime Search for missing Australian and US surfers ends in tragedy as bodies identified in Mexico

Wong made it clear that Canberra is committed to ending the prosecution. At the same time, she stressed that the Australian government cannot interfere in ongoing legal proceedings in the United Kingdom.

The US judiciary wants to try Assange on espionage charges, and if convicted, he faces up to 175 years in prison.

The 52-year-old is accused of stealing and publishing secret material from US military operations in Iraq and Afghanistan, together with whistleblower Chelsea Manning, thereby putting the lives of US informants in danger. Conversely, supporters of Assange see him as a journalist who brought war crimes to light.

Since his arrest in 2019, Assange has been held in the high-security Belmarsh prison in London. He previously spent several years in Ecuador's embassy in London to avoid arrest.

Most recently, he failed in an appeal against his extradition in the London High Court. This decision is now to be reviewed.

If his appeal is again rejected, the only option would be to appeal to the European Court of Human Rights.