A court spokesperson confirmed the new date for the three-week second part of the Australian's hearing with AAP on Wednesday.

The spokesperson added that a new venue is yet to be fixed.

It's understood that the search is difficult due to the huge backlog of cases in the UK, exacerbated by the coronavirus lockdown.

District Judge Vanessa Baraitser also wants to try to limit Assange's travel time between prison and the courtroom.

Last week she ordered his extradition hearing, originally set for May 18, to be delayed after applications by both legal teams.

Judge Baraitser admitted the lockdown could hinder legal parties from attending next month's hearing in person.

Defence barrister Edward Fitzgerald has consistently spoken of difficulties in meeting Assange in Belmarsh prison, even before lockdown began.

The Australian's father John Shipton is optimistic about a bail application, but it's still uncertain whether Assange will make a fresh bail bid on the grounds of improving his access to legal counsel.

Judge Baraitser denied an earlier bail application, saying she couldn't see how lockdown affected Assange's case preparations.

The Australian hasn't been seen since March 25 with his lawyers saying he's "too unwell" to appear in court via videolink.

Judge Baraitser scheduled a callover hearing on June 1 if he is well enough to attend via videolink.

WikiLeaks editor Kristinn Hrafnsson described the court's administration of the hearing as "chaotic".

"Julian could not attended the last hearing even by video link because of health concerns, no lawyer was in court because of the lockdown and most journalists could not join the conference call to listen to proceedings because of a foul-up in the court's technical facilities," he said.

"Justice has to be seen to be done. It wasn't, and we've always said that a fair trial would not be possible at the time the judge originally set."

Assange faces 17 charges of violating the US Espionage Act and one of conspiring to commit computer intrusion.

The 48-year-old is accused of publishing thousands of secret US diplomatic and military files, some of which revealed alleged war crimes in Iraq and Afghanistan.

The charges carry a total of 175 years' imprisonment.

Australian Associated Press