China has labelled concerns about Beijing's alleged espionage and interference in Australia a "shoddy soap opera", and dismissed claims that a detained Australian citizen is being held in inhumane conditions.

Key points: China says detained Australian citizen Yeng Hengjun is not being mistreated

China says detained Australian citizen Yeng Hengjun is not being mistreated China's foreign ministry says espionage claims are "bizarre and outlandish"

China's foreign ministry says espionage claims are "bizarre and outlandish" A spokesperson likened them to a "ridiculous farce or a shoddy soap opera"

China's Foreign Ministry spokesperson Hua Chunying made the comments in a daily Chinese foreign ministry briefing on Monday, where she was asked about Australia's new ASIO-led Counter Foreign Interference Taskforce.

She was also asked about the plight of Yang Hengjun, an Australian pro-democracy activist who has been held in Chinese detention since August 23.

Yang Hengjun's family lost contact with him in January following his arrival in Guangzhou. ( Supplied: Twitter )

Foreign Minister Marise Payne said yesterday Dr Yang was being held in "unacceptable" circumstances, which included increasing isolation from the outside world with daily interrogations, including while shackled.

Asked about Ms Payne's comments and other claims that Dr Yang may be being subjected to torture, Ms Hua said the Australian detainee was to her knowledge "in good physical condition".

"The so-called torture is simply non-existent," she said.

"China's national security organ handles the case in accordance with law and fully guarantees Yang's rights."

Dr Yang's supporters are growing increasingly anxious about whether or not the 54-year-old, who became an Australian citizen in 2002, has been subjected to torture.

His lawyer told the ABC that not one letter of support — including multiple from his immediate family — has been passed on to Dr Yang.

Espionage stories a 'shoddy soap opera'

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 4 minutes 53 seconds 4 m 53 s Feng Chongyi, a friend of Yang Hengjun, said the detainee could be subject to a "variety of torture".

On Monday, the Federal Government announced Australia's domestic spy agency ASIO would lead a new taskforce aimed at strengthening Australia's response to the threat of foreign interference.

While she did not directly refer to the taskforce when asked about it, Ms Hua criticised the media commentary around allegations of Chinese interference in Australia.

"For quite some time, certain Australian media and other agencies have been hyping up the so-called China espionage cases, China infiltration stories or China interference theory," Ms Hua said.

"No matter how bizarre and outlandish, they are just one ridiculous farce or shoddy soap opera after another."

Ms Hua also hit out at recent allegations raised in Australian media by a man claiming to be a former Chinese spy, saying it was "very likely" he had made the comments in order to gain Australian residency.

Wang Liqiang, who said he served as a Chinese intelligence operative for five years, is reportedly now in hiding and seeking asylum in Australia.

China has dismissed Wang Liqiang's claims about Beijing's alleged espionage operations. ( Supplied: 60 Minutes Australia )

His allegations, which range from Chinese interference in Australian domestic politics to Beijing's infiltration in the Hong Kong protest movement, have triggered a raft of commentary about alleged Chinese espionage after first being reported by the Nine Newspapers.

In the days since his allegations were made on November 24, China has sought to discredit Mr Wang, with Chinese state media releasing a courtroom video that purports to shows him confessing to fraud.

Mr Wang has rejected the allegations raised by Chinese authorities.