The sentence may be commuted to life imprisonment after two years, according to Australian officials as quoted by BBC.

The Australian writer has denied the charges levelled against him.

Australia reacts

Australian Foreign Minister Penny Wong said her government will be communicating its response to China in 'strongest terms'.

"Dr Yang has been detained since January 2019 on national security charges. His verdict and sentence have been subject to repeated delays since his closed trial on 27 May 2021," Wong said in a statement.

She said: "The Australian Government will be communicating our response in the strongest terms."

"The Australian Government has advocated for Dr Yang with China at every opportunity, and at the highest levels. We have consistently called for basic standards of justice, procedural fairness and humane treatment for Dr Yang, in accordance with international norms and China's legal obligations," she said.

"We will continue to press for Dr Yang's interests and wellbeing, including appropriate medical treatment, and provide consular assistance to him and his family," she said.

One of the supporters of Yang Hengjun described his detention as "political persecution".

"He is punished by the Chinese government for his criticism of human rights abuses in China and his advocacy for universal values such as human rights, democracy and the rule of law," his friend, Sydney academic Feng Chongyi, told the BBC.

Reacting to the development, Human Rights Watch Asia Director Elaine Pearson told BBC: "He has had delayed and limited access to legal representation, a closed door trial - and Yang himself has alleged torture and forced confessions during his interrogations."