China charges Australian-Chinese writer Yang Hengjun with espionage

China has charged detained Australian-Chinese writer Yang Hengjun with espionage for "endangering" the country's national security and engaging in "criminal activities".

China's Foreign Ministry spokeswoman Hua Chunying offered no further details about Yang at a daily news briefing in the capital.

She said that Yang is being investigated by "the Beijing State Security Bureau in accordance with the law on suspicion of engaging in criminal activities that endanger China's national security. This case is still under investigation".

She said all his legal rights have been fully guaranteed, adding that the Chinese side has officially notified the Australian Embassy in China.

"China and Australia have unimpeded channel for consular communication. China has provided necessary assistance for the Australian side to fulfill consular duties," Hua added.

Australia is seeking more information from Beijing after Defence Minister Christopher Pyne raised Yang's detention with Chinese Defence General Wei Fenghe on Thursday, news.com.au reported.

Pyne requested that Yang be treated fairly and transparently and have immediate access to consular assistance.

"General Wei assured that, while he was not personally aware of the case, Mr Yang would be treated well and that the general would seek further information," a spokesman for the minister said.

An Australia-China consular agreement requires either government be told within three days if one of their citizens is detained.

Chinese authorities took four days before alerting Canberra.

"Obviously that is disappointing and we will be raising that too with Chinese government officials," Pyne said.

Yang's case is in the hands of the Beijing city branch of the national intelligence bureau.

Yang, 53, had been living in New York as a visiting scholar at Columbia University with his wife and her child and had returned to China last week.

He had left New York on January 18 for Guangzhou, where he was prevented from boarding his connecting flight to Shanghai with his wife and daughter. Yang is said to be under "residential surveillance", which is similar to home detention.

Australian Foreign Minister Marise Payne on Thursday requested for details of the charges brought against him.

Payne said that at this stage there was no evidence to suggest Yang's detention was connected to international tensions around Chinese telco Huawei.