(Bloomberg) --

Singapore said an air travel bubble with Hong Kong will proceed as planned on Sunday, but arriving passengers from Hong Kong must now take a Covid-19 test as cases in the city increase.

Hong Kong has a “comprehensive public health surveillance system” and the overall incidence rate is still low, the Civil Aviation Authority of Singapore said in a statement on Saturday, explaining why the travel bubble will go ahead.

“The additional requirement is a precautionary measure given the rise of Covid-19 cases in Hong Kong over the past few days,” the CAAS said. “More cases are expected in Hong Kong over the next few days due to the emergence of new clusters. The Singapore and Hong Kong health authorities are in close contact and monitoring the situation.”

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Travelers departing Hong Kong for Singapore are already required to take a pre-departure Covid-19 test and must have a negative result.

The air travel bubble will be suspended if the seven-day moving average of unlinked virus cases exceeds five per day. CAAS said Hong Kong’s figure currently stands at 2.14 and will be exceeded if there are over 22 unlinked cases over the next three days. If breached, a two-day notice period will be triggered followed by a suspension of the travel bubble.

“Prevailing border measures – a 7-day Stay-Home Notice in the case of travelers from Hong Kong – will then apply upon entry into Singapore,” the CAAS said.

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