Almost 40 states have written to the United Nations supporting China's policies in the western region of Xinjiang, a Chinese diplomat told the U.N. Human Rights Council on Friday.

China has been accused of detaining a million Muslims and persecuting ethnic Uighurs in Xinjiang, and 22 ambassadors signed a letter to the Council this week criticising its policies. China says local citizens are simply going through vocational training to stop them being radicalised.