New Zealand 'will not compromise' on suspending extradition treaty with Hong Kong unless new security law revoked, says Winston Peters

New Zealand will not back down on its suspension of the extradition treaty with Hong Kong despite China's threat of consequences, says Winston Peters.

The Minister of Foreign Affairs told The AM Show on Wednesday the only thing that would make him backtrack on the suspension would be the reversal of Beijing's controversial new security law.

The law will punish acts of state subversion, separatist activity and collusion with foreign forces. Anyone convicted of protesting against, or helping someone else protest the new law could be extradited to mainland China and judged there, rather than in Hong Kong. The maximum penalty is life imprisonment and Chinese courts have a near 100 percent conviction rate. 

Peters says New Zealand could not support such a change. 

"We can't stand by and compromise our beliefs in democracy and freedom and the rule of law and the fair trial of someone in Hong Kong."

He says New Zealand was promised Hong Kong and China would operate under a "one country, two systems" framework - but now this has been scrapped, China must understand New Zealand's point of view. 

"We were given a commitment that Hong Kong would be allowed to have the freedom of governance locally and their own system of laws. (China has) just changed that - please don't think that when we react to it by way of judgement is us trying to interfere - quite the contrary."

Peters says the law change will have a huge impact on Hong Kong and it's people. 

"Unless there is a reconciliation back to the original commitment then Hong Kong will never be the same which is terribly, terribly  sad." 

New Zealand's suspension of the treaty has been blasted by China's Foreign Ministry spokesperson Wang Wenbin who said on Wednesday it is "a serious violation of international law" and "a gross interference in China's internal affairs".

He urged New Zealand to "immediately correct its mistake and stop interfering in China's Hong Kong affairs to avoid damage to bilateral relations". 

The increase in tensions has raised concern from some over how New Zealand could be penalised for what China sees as interference. 

International relations expert Stephen Hoadley says China's response to Australia suspending its treaty could indicate how it will treat New Zealand. 

"There were great tariffs put on its barley export, there was slow down of the movement of Australian goods across the docks in China, there was a lot of rhetorical condemnation and the Beijing government has recommended that Chinese people do not travel there," he told The AM Show on Monday.

Just before New Zealand announced the treaty would be suspended, Chinese state media was talking up New Zealand as a strong competitor to take Australia's market share of agricultural products.

Hoadley says there could be light at the end of the tunnel, as China has a reputation to maintain. 

"What's in New Zealand's favour is that China is very dependent on exporting, on trade, and the more it punishes countries like Australia and New Zealand, whoever crosses them on their Hong Kong issues, the more it will tarnish China's reputation as a reliable trader."