An Inbound passenger fills out an epidemiological investigation form at customs in Guangzhou Baiyun International Airport in Guangdong province, on March 28, 2020. [Photo/Xinhua]

China's aviation regulator ordered on Monday a one-week suspension of a US-Bangla Airlines flight from Dhaka, Bangladesh, to Guangzhou in an effort to prevent imported COVID-19 cases, the first "circuit-breaker" directive towards an overseas carrier.

A total of five passengers on the June 28 flight from Bangladesh's capital to the provincial capital of Guangdong tested positive for the novel coronavirus, meeting the conditions for a "circuit breaker" suspension of the flight route, the Civil Aviation Administration of China said in a statement.

In keeping with an international flights adjustment policy announced on June 4, the administration issued its third "circuit-breaker" directive and announced the one-week suspension would begin on Monday.

In early June, China eased restrictions on international passenger flights contingent on epidemic risks being under control. Authorities highlighted the "reward and circuit breaker mechanism" for the carriers to increase or have flights suspended in accordance with the companies' epidemic control work.

Under the policy, airlines must suspend flights on a route for a week if five passengers test positive for coronavirus. If the number exceeds 10, the airline must suspend the flights for four weeks.

As an incentive, carriers may increase the number of international flights to two per week on a route if for three consecutive weeks no passengers test positive for the virus in nucleic acid tests.

On June 14, the administration issued its first "circuit-breaker" directive and demanded a four-week suspension of a China Southern Airlines flight, also from Dhaka to Guangzhou, as 17 passengers tested positive for the novel coronavirus, and later gave out the second directive for a one-week suspension of a Sichuan Airlines flight from Egypt's capital, Cairo, to Chengdu in Southwest China's Sichuan province on Wednesday.