MANILA (UPDATE) — The arrival of AstraZeneca’s COVID-19 vaccines will be delayed, Health Secretary Francisco Duque III said on Sunday.

Officials earlier said 520,000 doses from Britain's AstraZeneca would arrive on Monday. But Duque said the World Health Organization informed them late Sunday afternoon that it was having problems with the supply.

"Kanina, tumanggap kami ng komunikasyon, nagsasabi e hindi raw matutuloy, baka abutin ng isang linggo pa," he said in an interview on government network PTV.

(Earlier, we got a message saying it won't push through. It may take another week.)

Vaccine czar and national COVID-19 task force chief implementer Carlito Galvez Jr. declined to give the reason behind the delay, saying WHO and UNICEF will explain the postponement.

"We have to understand kasi nakita natin yung logistical chain ng ating COVAX facility considering na talagang yung vaccination ngayon globally ay naga-accelerate yan," he told reporters.

(We have to understand since we've seen the logistical chain of COVAX Facility, considering vaccinations globally have accelerated.)

There is no definite arrival date yet for AstraZeneca's jabs, Galvez said, imploring the public to wait.

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The Philippines on Sunday received its first vaccine delivery, courtesy of China's donation of 600,000 shots developed by Beijing-based drug maker Sinovac Biotech.

Authorities have also negotiated vaccine supply deals with other manufacturers. The Philippines seeks to secure up to 148 million doses so it can inoculate at least 70 million people, or two-thirds of its population.

The Philippines is the last Southeast Asian country to receive initial vaccine supplies.

• Philippines last in region to get COVID-19 shots? 'No big meaning,' says Palace

The archipelago, which has the second-highest tally of infections and deaths in the region, has suffered lengthy lockdowns, hitting hard a consumption-driven economy.

Despite the arrival of the vaccines, there is little public support for the inoculation drive. One opinion poll showed that less than a third of Filipinos are willing to get vaccinated as they worry about potential side effects.
— With a report from Reuters