China assailed the United States on Tuesday for calling on countries to deprive Beijing of a seat at a U.N. forum over its treatment of the Uighur minority.

It was the second time in as many weeks that the two countries openly clashed at the United Nations over the rights of the Uighurs and other mostly Muslim minorities held in camps in China’s Xinjiang region.

U.S. diplomat Courtney Nemoff said ahead of elections on Tuesday that China’s treatment of Uighurs should be a factor in deciding on membership to the forum tasked with protecting indigenous people worldwide.

“The United States is alarmed that more than a million Uighurs, ethnic Kazakhs, Kyrgyz and other Muslims have suffered arbitrary detention, forced labor, torture and death in camps in China’s Xinjiang” region, said Nemoff. “These atrocities must be stopped. We call on member states to bear this in mind in this important forum.”

A Chinese diplomat took the floor to strongly reject the U.S. statement.

“The U.S. representative made an unreasonable accusation against China and defamation against China,” he said, expressing Beijing’s “strong displeasure over this and our firm opposition to it.”\

“The U.S. representative made an unreasonable accusation against China and defamation against China,” he said, expressing Beijing’s “strong displeasure over this and our firm opposition to it.”

Despite the U.S. appeal, China’s candidate, Zhang Xiaoan, was elected by acclamation to the 16-member U.N. forum along with four other representatives from Burundi, Namibia, Denmark and Russia.