A Chinese diplomat repeatedly interrupted a speech by a prominent Chinese dissident to block him from addressing the UN human rights council, in a failed attempt that bared China’s sensitivity on human rights.

Yang Jianli, a dissident in exile in the United States, was disrupted seconds into his remarks as he questioned the Chinese Communist party’s right to represent China at the UN body. Yang was invited to appear before the human rights council meeting by UN-accredited advocacy group UN Watch.

Chen Cheng of China’s diplomatic mission stepped in and insisted that Yang’s intervention “seriously affected the reputation of council, and it should be firmly opposed”.

Yang went on to cite events from decades of recent Chinese history, including the Great Leap Forward, the Cultural Revolution and the crackdown on the Falun Gong and democratic movements.

“Millions of people have died,” he said.

Chen interrupted again, appealing to the chair to “rule against his speaking”.

Invited to continue speaking instead, Yang warned that China “will return to the road of personal dictatorship” to control speech and crack down on activists, churches in Xinjiang and Tibet. He did not elaborate in the time-limited address.

Chen insisted that Yang was speaking outside the topic of the session. Both spoke in Chinese, and their comments were translated.

Yang participated in the pro-democracy demonstrations in Tiananmen Square in 1989 and served five years in prison in China.

Tuesday’s conflict came during debate about the Vienna declaration and program of action, which says non-governmental organizations “should be free to carry out their human rights activities, without interference”.