Pompeo did not give a reason for US Ambassador to China, 73 years old and a former governor of Iowa, leaving china at a time when relations are strained, notably over bilateral trade, allegations about information security, and the coronavirus pandemic. The US embassy did not immediately respond to a request for comment.

“I thank Ambassador Terry Branstad for his more than three years of service to the American people as US Ambassador to the People’s Republic of China,” Pompeo tweeted, Reuters reported.

“Ambassador Branstad has contributed to rebalancing US-China relations so that it is results-oriented, reciprocal, and fair,” he added, without explicitly saying Branstad was going.

Citing an unnamed source, the CNN news network reported that Branstad was likely to leave before the November US presidential election.

The Chinese foreign ministry has in the past described Branstad as an “old friend of the Chinese people”.

He first forged ties with President Xi Jinping several decades ago when Xi visited Iowa.

Last week, the United States and China traded attacks about who best understands press freedom after the official People’s Daily refused to publish an article by Branstad.

China’s foreign ministry spokesman Wang Wenbin told a daily news conference that China had not received a notice about Branstad leaving.