Passengers of China-bound flights must provide negative COVID-19 test results before boarding, China's aviation authority said on Tuesday.
It comes as the government looks to further reduce the risk of imported coronavirus cases amid increased international travel.
Nucleic acid tests must be completed within five days of embarkation, the Civil Aviation Administration of China (CAAC) said on its website.
Tests should be conducted at facilities designated or recognised by Chinese embassies in host countries, it said.
The embassies will carefully assess the testing capacity of host countries and formulate travel procedures when testing conditions are met, CAAC said.
The announcement comes as countries struggle with testing capacity and speed. In parts of the United States, receipt of test results can take up to two weeks, while in some other countries, nucleic acid tests are reserved for people who have come in close contact with COVID-19 patients or who have symptoms of the potentially fatal disease.
In the past month, CAAC has allowed more foreign airlines to resume services in China and add flights to the country as the economy recovers.

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