NEW YORK (Reuters) - The United States led more than 30 countries in condemning what it called China’s “horrific campaign of repression” against Muslims in Xinjiang at an event on the sidelines of the U.N. General Assembly that was denounced by China.

FILE PHOTO: A propaganda banner and a security camera are placed on the walls of a mosque in the Old City in Kashgar, Xinjiang Uighur Autonomous Region, China September 6, 2018. Picture taken September 6, 2018. REUTERS/Thomas Peter

In highlighting abuses against ethnic Uighurs and other Muslims in China, Deputy Secretary of State John Sullivan said on Tuesday the United Nations and its member states had “a singular responsibility to speak up when survivor after survivor recounts the horrors of state repression.”

The United Nations says at least 1 million ethnic Uighurs and other Muslims have been detained in what China describes as “vocational training centers” to stamp out extremism and give people new skills.

Sullivan said it was incumbent on U.N. member states to ensure it was able to closely monitor human rights abuses by China and added that it must seek “immediate, unhindered, and unmonitored” access to the western region of Xinjiang for the U.N. High Commissioner for Human Rights.

Sullivan said Tuesday’s event was co-sponsored by Canada, Germany, the Netherlands and Britain, and was joined by more than 30 U.N. states, representatives of the European Union and more than 20 nongovernmental organizations, as well as Uighur victims.

“We invite others to join the international effort to demand and compel an immediate end to China’s horrific campaign of repression,” he said. “History will judge the international community for how we respond to this attack on human rights and fundamental freedoms.”

China’s Foreign Ministry denounced the U.S. move.

The Xinjiang issue is not about human rights but about countering separatism and terrorism, Chinese Foreign Ministry spokesman Geng Shuang told a daily news briefing in Beijing on Wednesday.

“All the slander and defamation of the U.S. and other countries is futile.” said Geng. “Their lies will crumble in the face of facts and truth.”

“RELIGIOUS LIBERTY”

Paola Pampaloni, deputy managing director for Asia of the European External Action Service, said the EU was “alarmed” by the situation and also urged “meaningful” access to Xinjiang.

“We are concerned about ... information about mistreatment and torture,” she said. “China is always inviting us to the camps under their conditions, we are in negotiations right now for terms and conditions for free access.”

On Monday U.S. President Donald Trump called for an end to religious persecution at another event on the sidelines of the U.N. gathering. He reiterated his comments in a speech to the General Assembly gathering of world leaders on Tuesday.

“Americans will never ... tire in our effort to promote freedom of worship and religion. We want and support religious liberty for all,” he said.

Trump, who has been cautious about upsetting China on human rights issues while making a major trade deal with Beijing a major priority, said religious freedom was under growing threat around the world but fell short of specifically mentioning the Uighur situation.

“Volume is coming up at a pace that we hope that the Beijing government recognizes not only U.S. but the global concern about this situation,” David Stilwell, U.S. Assistant Secretary, Bureau of East Asian and Pacific Affairs told reporters.

“We will see how that plays out and how Beijing reacts and take it from there.”

A representative for the Chinese delegation to the U.N. General Assembly accused Washington of violating the U.N. Charter by criticizing China.

Sullivan said the United States had received “credible reports of deaths, forced labor, torture, and other cruel, inhumane, or degrading treatment” in the camps.

He said there were also many reports that the Chinese government forces detainees to renounce their ethnic identities as well as their culture and religion.

Though U.S. officials have ramped up criticism of China’s measures in Xinjiang, it has refrained from responding with sanctions, amid on-again, off-again talks to resolve a bitter, costly trade war.

At the same time, it has criticized other countries, including some Muslim states, for not doing enough or for backing China’s approach in Xinjiang.

Rishat Abbas, the brother of Uighur physician Gulshan Abbas, who was abducted from her home in Urumchi in September 2018, told Tuesday’s event that “millions of Uighurs are becoming collateral damage to international trade policies, enabling China to continue to threaten our freedoms around the world, enable it to continue its police state.”

U.N. human rights chief Michelle Bachelet has repeatedly pushed China to grant the United Nations access to investigate reports of disappearances and arbitrary detentions, particularly of Muslims in Xinjiang.

China’s envoy in Geneva said in June that he hoped Bachelet would visit China, including Xinjiang. Bachelet’s office said in June that it was discussing “full access” with China.