“We have been raising concerns about his kidney health and requesting medical parole for several years and have had no reliable assurances that he is getting any of it.

“And now,in recent days,we are told that he has a kidney cyst that is roughly the same size as the kidney itself. We have not been told what kind of cyst this is or what treatment options are available.”

Sources said that after Yang complained of a persistent muscle strain,a doctor conducted a medical examination and told him he had a 10-centimetre cyst.

Although the cyst is so large that it is squeezing his kidney,the doctor said no action was required as long as it wasn’t too painful and didn’t split or bleed.

This was the first time Yang had been advised of the results after being given several medical examinations during his time in detention,supporters said.

Yang’s doctoral supervisor Feng Chongyi said:“We ask that the Australian government leverages its new openings for dialogue to raise three urgent demands:

• obtain access to review the full medical examination report and other recent reports;
• ensure Yang is given Australian-supervised medical treatment outside the detention centre (supervised by an Australian-approved expert);
• and procure Yang’s release to Australia on medical parole.

“These are the three things that need to be done to ensure that an Australian citizen is not left to die as a political prisoner in a Beijing detention centre.”

The Beijing People’s High Court has approved multiple extensions to the deadline for handing down a verdict on Yang’s case,with October 9 set as the current deadline for a verdict.

Yang,who completed a PhD at the University of Technology Sydney,has spent the past four years in a 1.2 metre-wide prison cell with two other prisoners.

His supporters said he is frequently hungry between meals because the detention centre has stopped selling extra food.

A spokeswoman for Foreign Minister Penny Wong said:“Our thoughts are with Dr Yang Jun,and we share the deep concerns of his friends and family about the ongoing delays in his case.

“The Australian government has consistently advocated for Dr Yang’s interests and wellbeing,and for him to be reunited with his family.

“His case has been raised at every opportunity with the Chinese government,including by the prime minister and foreign minister.”

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