US President Joe Biden violated the norms of diplomatic etiquette after his statements about the leader of the People's Republic of China Xi Jinping, Chinese Foreign Ministry spokeswoman Mao Ning said at a briefing.

"Such statements by the U.S. side are extremely irresponsible and they also violate basic norms of diplomatic etiquette," she said.

The Chinese foreign ministry spokeswoman expressed "serious dissatisfaction" with Biden's words and made a "strong protest."

U.S. President Joe Biden told PBS that he had threatened Chinese President Xi Jinping with the loss of Western investment if he supported Russia in Ukraine.

Biden also said that Xi Jinping has "huge problems." "He also has great potential. But so far he's not doing too well in the economy," the U.S. leader said.