No new date has been set for the bubble to start as the SAR's Commerce and Economic Development Bureau said - following a virtual meeting between its head, Edward Yau Tang-wah, and Singapore's Minister for Transport, S Isawaran yesterday morning - "a further announcement will be made on or before June 13."

Hong Kong yesterday also moved Singapore from low-risk to high-risk and, starting Friday, arrivals will be required to test negative 72 hours before boarding flights and observe a 21-day hotel quarantine upon arrival.

With the change, non-Hong Kong residents will not be allowed to fly in from Singapore. The same policy will apply to Argentina, Italy, Japan, Kenya and Malaysia from Friday.

Those who are fully vaccinated and have waited 14 days to generate sufficient antibodies can have their hotel quarantine shortened to 14 days.

The Hong Kong-Singapore bubble was first scheduled for launch in November, but was put on hold due to the fourth wave of outbreaks in Hong Kong.

This time the deferral came after Singapore saw growing community infections and, from Sunday, tightened anti-epidemic measures - a two-person gathering cap, a dine-in ban, mandatory work from home and home-based school - that will last until June 13.

Singapore yesterday reported 28 new cases.

Under the agreement, if the seven-day moving average of the daily number of unknown source local infections was more than five for either Singapore or Hong Kong, the scheme would be suspended for 14 days.

Singapore's ministry of health on Sunday said the number of new community cases was 131 last week, compared with 39 the week before.

The chairman of Hong Kong's Travel Industry Council, Jason Wong Chun-tat, said he hoped the bubble could be launched before the summer holidays and suggested Hong Kong prioritize travel bubble arrangements with the mainland or other countries where the Covid-19 situations have stabilized.