Politicians pen letter urging Jacinda Ardern to stop accused murderer Kyung Yup Kim's extradition to China

Politicians from 14 different countries have penned a letter to Prime Minister Jacinda Ardern urging New Zealand not to send accused murderer Kyung Yup Kim back to China.

Chinese authorities want Kim, who's lived in New Zealand for over 30 years, to face trial there - but there's concern he could suffer torture and not get a fair trial.

Kim is a man with an uncertain future. China has fought for 10 years to extradiate him to face trial there for murder.

His lawyer says he suffers from depression and other severe health problems.

"A brain tumour, small one, and a liver and kidney disease," said Tony Ellis.

New Zealand's Supreme Court last week upheld a decision to surrender him to China. That news was met with outrage around the world.

In a letter to our Government signed by politicians from 14 different countries including the UK, France and Australia, they urged that Kim not be extradited, saying "it is beyond doubt that China commits gross, flagrant or mass human rights abuses."

They also said following through with extradition "would set a dangerous precedent" that may have far-reaching implications for human rights beyond New Zealand's borders.

But the Supreme Court ruled the Minister could be satisfied by China's assurances that Kim would receive a fair trial and treatment. His lawyer, though, disagrees.

"Besides being tortured, your chances of getting a fair trial are non-existent," said Ellis.

The case has grabbed international headlines, all reporting on the Supreme Court's decision. 

On Friday the Prime Minister gave the strongest hint yet she won't intervene.

"All of these questions have been raised and considered as part of our court's consideration of the extradiation. I obviously have great faith that our court processes have weighed up all of those," Ardern said.

Kim is accused of murdering Peiyun Chen while visiting Shanghai in 2009.

In an exclusive interview last year provided by Chinese Interpol, Chen's sister worried her parents wouldn't live long enough to see her accused killer face trial.

Kim has always maintained his innocence and will now take his matter to the UN Human Rights Committee.

"The Committee would ask New Zealand not to extradite him pending a fuller hearing," Ellis said.

The ball is in the Justice Minister's court to determine if Kim is fit to be sent back to China.