The prime minister has vowed to keep advocating for the release of Australian Yang Hengjun, after the jailed writer decided not to appeal his suspended death sentence.

Dr Yang was found guilty of espionage charges in China in February after spending five years in prison.

He will still face the prospect of life behind bars at the end of a two-year suspended death sentence.

In a letter written by Dr Yang’s family and friends, they said they supported the imprisoned writer’s decision to waive his right to appeal.

“Commencing an appeal would only delay the possibility of adequate and supervised medical care, after five years of inhumane treatment and abject medical neglect,” it reads.

Anthony Albanese said work will continue from officials in calling for his release from prison.

“We will continue to make representations to China that, in his interests, the Australian government will always stand up for the rights of Australian citizens,” he told ABC Radio on Wednesday.

“We object in the strongest possible terms to the sentence that was handed out to him.”

Foreign Minister Penny Wong said the government respects the “difficult decision” Dr Yang made.

“I acknowledge the strength that Dr Yang’s family and friends have demonstrated through this period,” she said.

“All Australians want to see Dr Yang reunited with his loved ones.”

Dr Yang’s family has described the charges levelled against him as being without factual basis, and say there’s little evidence of the justice system in China containing the rule of law.

“Yang was subjected to hundreds of instances of torture and has never received any semblance of due process,” the letter said.

“The accusations that the Beijing Municipal State Security Bureau has levelled against him are so spurious that they have never been publicly disclosed, let alone properly tested and cross-examined in court.”

Dr Yang’s supporters have urged China to provide him with medical care, saying he had been denied proper treatment for a serious kidney condition throughout his time in prison.

Australian embassy officials have met with Dr Yang monthly, while Trade Minister Don Farrell is expected to raise the plight of the writer with his Chinese counterpart Wang Wentao on the sidelines of a World Trade Organisation forum in Abu Dhabi at the end of the month.

China has maintained the case was held in accordance with its legal system.

Dr Yang’s family expressed thanks to the Australian government for campaigning on his behalf.