Julian Assange has missed his court hearing via a video link from a British prison, with his lawyers saying his health has deteriorated severely.
Assange's lawyer Gareth Peirce said he is now incapable of even holding a conversation.
WikiLeaks said he had been moved to a health ward at Britain's Belmarsh prison, and he has lost a lot of weight.
Assange was scheduled to appear in court for a US extradition hearing over hacking and espionage charges.
The next hearing on the extradition request was set for June 12.