New Zealand on Tuesday became the fourth country to scrap its extradition treaty with semi-autonomous Hong Kong because of China’s new national security law for the region, Reuters reported. Australia, Canada and the United Kingdom had suspended their extradition treaties with Hong Kong earlier this month.

New Zealand’s Foreign Affairs Minister Winston Peters said that his country can no longer believe that Hong Kong’s criminal justice system is free from Chinese influence. “If China in future shows adherence to the ‘one country, two systems’ framework then we could reconsider this decision,” he added.

The Chinese Embassy in New Zealand, meanwhile, said that the country’s move was a serious violation of international law. “It is a gross interference in China’s internal affairs,” the embassy said in statement. “The Chinese side has lodged its grave concern and strong opposition.”

In June, China’s Parliament passed a national security legislation for Hong Kong that would override local laws and give sweeping powers to security agencies. The unprecedented law is aimed at curbing protests – which rocked Hong Kong last year – and prohibiting subversion, separatism, “acts of foreign interference”, and terrorism. These charges are often used in the Chinese mainland to stifle dissidents and political opponents. The new law will also allow China’s security personnel to operate in Hong Kong.

Under the new law, certain political views and symbols, including those showing support for the independence of Hong Kong, Taiwan, Xinjiang and Tibet from China, are now illegal. Officials in Hong Kong and Beijing have said the law is vital to plug gaps in national security exposed by the protests. Critics say China’s law ends the freedoms that were guaranteed for 50 years under the “one country, two systems” agreement when British rule ended in 1997.

Earlier this month, United States President Donald Trump had signed an order to end special trade preferences for Hong Kong to punish China for its “oppressive actions”.