Foreign Affairs Secretary Teodoro Locsin Jr. said the government of Hong Kong won't honor the proof of vaccination issued by local government units and the Bureau of Quarantine because it is not "connected to a single source." On Wednesday, he said he will formally ask Hong Kong's chief executive Carrie Lam about the matter.

This obstacle delays the departure of over 3,000 Filipino workers who were scheduled to fly back to their employers in Hong Kong starting Monday.

Philippine Consul General in Hong Kong Raly Tejada said the special administrative region is open to accepting the World Health Organization-recognized International Vaccine Certificate or "yellow card" issued to fully vaccinated OFWs. However, the Bureau of Quarantine needs to include the traveler's passport number, he added.

"Good that Hong Kong is amenable to accepting our WHO International Vaccine Certificate, which our Bureau of Quarantine is currently issuing, provided it includes the passport details of the holder," he said. "We are now consulting with the BOQ to have the passport details of the holder incorporated in the yellow card."

The Philippines is classified by the Hong Kong government as "high risk" for COVID-19. It requires foreign workers from the Philippines with visa to present a "recognized vaccination record" and undergo 21 nights of hotel-based quarantine.