American diplomatic staff have left their consulate in the Chinese city of Chengdu, after a 72-hour deadline expired.
China ordered the closure in response to the US closing the Chinese consulate in Houston, Texas, last week.
Before Monday’s deadline, staff were seen leaving the building, a plaque was removed, and a US flag was lowered.
China’s foreign ministry said Chinese staff entered the building after the deadline and “took over”.
A US state department spokesperson said: “The consulate has stood at the centre of our relations with the people in Western China, including Tibet, for 35 years.
“We are disappointed by the Chinese Communist Party’s decision and will strive to continue our outreach to the people in this important region through our other posts in China.”
As the US consulate closed, crowds of local residents gathered outside, with many waving Chinese flags and taking selfies.
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Last Wednesday the US ordered the Chinese consulate in Houston to close, alleging that it had become a hub for spying and property theft.
Tensions have been escalating between the two countries over a number of issues:
US President Donald Trump’s administration has clashed repeatedly with Beijing over trade and the coronavirus pandemic
Washington has also condemned the imposition by China of a controversial new security law in Hong Kong
Last week, a Singaporean man pleaded guilty in a US court to working as an agent of China
Also last week, four Chinese nationals were charged in a separate case with US visa fraud for allegedly lying about serving in China’s military