U.S. Secretary of State Mike Pompeo on Thursday called China's treatment of its Uighur Muslim minority the "stain of the century" and accused Beijing of pressuring countries not to attend a U.S.-hosted conference on religious freedom.
"China is home to one of the worst human rights crises of our time; it is truly the stain of the century," Pompeo told the final day of the international conference in Washington.
Pompeo said Chinese government officials had sought to discourage countries from attending the three-day event he has hosted.
"Is that consistent with the guarantee of religious belief that is found directly in the Chinese constitution?" he asked.
Pompeo congratulated countries which had defied Chinese pressure, while adding: "If you have declined to attend for the same region, we take note."
Pompeo did not name any of the countries and the State Department did not immediately respond to a request for details.
Pompeo's remarks came a day after U.S. President Donald Trump met at the White House with victims of religious persecution from countries including China, Turkey, North Korea, Iran and Myanmar.
U.S. Vice President Mike Pence, who has been a strong critic of China, was also due to address the conference on Thursday morning.
Nearly two dozen nations at the U.N. Human Rights Council this month urged China to halt persecution of ethnic Uighurs in its western region of Xinjiang, where U.N. experts and activists say at least 1 million are held in detention centers.
The Trump administration has been weighing sanctions against Chinese officials over their policies in Xinjiang, including the Communist Party chief of the region, Chen Quanguo, but has held back amid Chinese threats of retaliation.
Relations between the United States and China are already tense over a tit-for-tat trade war, with the United States alleging that China engages in unfair trading practices.
