The 48-year-old did not appear for a routine call-over hearing at the Westminster Magistrates’ Court in London on Monday.
Assange is fighting extradition to the US to face 17 charges of violating the US Espionage Act and one of conspiring to commit computer intrusion.
Wikileaks founder Julian Assange leaves in a prison van after appearing at Westminster Magistrates Court in London. (AP)
The US Department of Justice made fresh allegations last week that Assange recruited hackers at conferences in Europe and Asia to provide WikiLeaks with classified information, including military secrets.
Judge Vanessa Baraitser said she had received an email about the superseding indictment, but not the document itself.
Prosecution barrister Joel Smith said both parties were still considering the impact of the superceding indictment.
“If we need to involve the court … then we will inform the court at the appropriate time,” he said.
Barrister Mark Summers said via telephone that the defence only heard it from media reports, but hadn’t been formally served with the new indictment.
“‘We are surprised by the timing of this development,” he told the court.
“We were surprised to hear about it in the press.”
Mr Summers said the fresh allegations could impact the upcoming case management hearings. The defence is due to provide the court with its final evidence on July 10.
WikiLeaks editor-in-chief Kristinn Hrafnsson said the new indictment had no new charges and hadn’t even been sent to Assange’s lawyers or the court yet.
“That just shows this is a glorified press release and not a new indictment at all,” he said in a statement.
“This shows how they are abusing due process in the UK and flaunting the legal system’s rules.”
Assange did not attend due to the coronvirus risk and hasn’t been seen in court for about three months.
Smith said that the prosecution’s psychologist hadn’t been able to assess Assange in prison due to the coronavirus lockdown.
Judge Baraitser said Belmarsh prison officials had emailed her to say that he was not unwell, he was refusing to attend.
She said Assange could only be absent if he was actually unwell, not if he was worried about becoming ill.
Judge Baraitser said he had to provide medical evidence if he did not attend the next call-over on July 27.
Mr Summers said that the defence could do that if required.
The Australian is accused of publishing thousands of secret US diplomatic and military files, some of which revealed alleged war crimes in Iraq and Afghanistan.
He’s also accused of trying to recruit hackers to provide WikiLeaks with classified US information.
The charges carry a total of 175 years’ imprisonment.
© AAP 2020