New Zealand is among a large group of states calling for China to urgently respond to findings of "serious human rights violations" against the Uyghur people in Xinjiang.
Fifty countries issued a joint statement at the United Nations (UN) overnight expressing concern that China is yet to discuss the findings of a report released in September.
China has reacted furiously, accusing the group of "maliciously" attacking the country and claiming Western nations are creating a "furore" to "destabilise China".
The joint statement, which was presented by Canada at the UN's committee on human rights, said the countries are "gravely concerned" about the situation in China, "especially the ongoing human rights violations of Uyghurs and other predominantly Muslim minorities in Xinjiang".
The collection of states behind the message is described by Human Rights Watch (HRW) as the "largest group of states to publicly denounce" China's human rights issue. The signatories include New Zealand, Australia, the United States, and the United Kingdom.
It follows a report from the UN Office of the High Commissioner for Human Rights (OHCHR) in September which found "serious human rights violations" are occurring in Xinjiang that potentially amount to crimes against humanity.
It said allegations of torture, forced medical treatments, and the use of arbitrary and discriminatory detention are credible and recommended all detained people be released.
China immediately derided the report as "disinformation and lies", claiming camps in Xinjiang are for vocational education and counter-terrorism purposes.
Tuesday's joint statement said China "has so far refused to discuss [the OHCHR's] findings".
"In that context, we urge the Government of China to uphold its international human rights obligations and to fully implement the recommendations of the OHCHR assessment.
"This includes taking prompt steps to release all individuals arbitrarily deprived of their liberty in Xinjiang, and to urgently clarify the fate and whereabouts of missing family members and facilitate safe contact and reunion."
Cuba, on behalf of 66 countries, including Russia, North Korea and Syria, presented a counter-statement in support of China. HRW labelled these countries are "a virtual rogues gallery of serious human rights abusers".
Later, in a statement, Dai Bing from China's Permanent Mission to the UN said the United States and other Western countries were attempting to create "a furore about Xinjiang is to destabilise China, obstruct her development and maintain their hegemony by exploiting human rights issues".
Dai also called the states "sore losers" after an attempt to hold a debate about the abuses in Xinjiang was last month voted down at the United Nations Human Rights Council. New Zealand is not a member of that council.
"The United States has launched 9 times of spiteful attacks against China with no regard for time and place," Dai said.
"Their petulant and desperate behaviour is - may I say - quite unbecoming. It's plainly visible to all that caring about human rights in Xinjiang is just a façade, behind which lies their true intent, namely, to contain China by making and spreading lies about Xinjiang and to maintain their hegemony. Today, it's China that's in the crosshairs of their punitive flak; tomorrow, it would be some other developing country."
He went on to say many of the signatories belong to a "club of former colonial powers".
"They consider themselves "human rights drillmasters". They seem to have forgotten the bloodbath, slave trade, plunder of resources and ethnocide that they once visited upon Asia, Africa and Latin America."
Following the release of the OHCHR report, New Zealand Foreign Affairs Minister Nanaia Mahuta expressed "deep concern" and called on China "to uphold its international human rights obligations and to respond to the concerns and the recommendations".
