China Warns Australia To 'Stop Interfering' In Arrest Of Yang Hengjun

China has warned Australia to respect its "judicial sovereignty" and not interfere in the case of a Chinese-Australian writer and democracy advocate charged with spying.

Academic Yang Hengjun could face the death penalty if the charges against him stand and Australian legal experts have called for the federal government to intervene.

The Chinese foreign ministry confirmed on Tuesday Yang who was detained in January has been formally charged with espionage.

READ MORE: Australian Activist Charged With Spying In China

"This case is being investigated. According to law, his rights are lawfully and fully guaranteed. He is in good health condition," foreign ministry spokesperson Geng Shuang said.

Geng warned Australia to "earnestly" respect China's legal process.

"China is a country with rule of law and Australia should earnestly respect China's judicial sovereignty and stop interfering in China's case-handling in any form," he said.

Yang Hengjun. Image: Twitter

China has a long history of arresting dissidents, some of them while they are residing abroad, to later charge them with various crimes.

Yang's Melbourne lawyer Rob Stary said the basis for the espionage charge was unclear.

"We think it relates to espionage on behalf of Australia, but it's not specified on the charge sheet," Stary told AAP on Tuesday.

"We'd obviously be disturbed by that, if it was the allegation, because there is absolutely no foundation for it at all."

Yang, 53, is a former China ministry of foreign affairs diplomat who became a pro-democracy campaigner and was made an Australian citizen in 2002.

The dual-national was detained in Guangzhou in January during a stopover while travelling from the U.S. to Australia. He has been held in Beijing since then.

READ MORE: 'Courageous' Australian Writer Yang Hengjun Detained In China

Yang Hengjun is currently being held by the Chinese government. (Image AAP)

Foreign Minister Marise Payne has serious concerns for Yang's welfare and the harsh conditions under which he has been held in Beijing for more than seven months.

"Since that time, China has not explained the reasons for Yang's detention, nor has it allowed him access to his lawyers or family visits," Senator Payne said.

"It is important, and we expect, that basic standards of justice and procedural fairness are met.

"I respectfully reiterate my previous requests that if Yang is being held for his political beliefs, he should be released."

Senator Payne has discussed his plight with China's foreign minister twice and has written to him three times.

Embassy officials have visited Yang seven times since his detention, most recently on July 25.

They had another visit approved for Tuesday.

Minister for Foreign Affairs Marise Payne. Photo: AAP

Law Council of Australia president Arthur Moses SC says the council stands with the federal government and is ready to provide any assistance needed.

"In China, espionage is punishable by death," Moses told AAP.

"The Law Council decries capital punishment and, as previously seen in other cases involving Australians facing the death penalty in other parts of the world, there is a dire need for early government intervention."

Dr Yang, who was a visiting scholar at Columbia University and living with his family in New York prior to his arrest, faces between three years in prison and the death penalty if found guilty of espionage by China's opaque judicial system.

He also has a doctorate from the University of Technology in Sydney.