MANILA (UPDATE)– The supposed delivery to the Philippines of 15,000 Sputnik V COVID-19 shots from Russia on Wednesday will be postponed, Malacañang confirmed.

Sources earlier told ABS-CBN News that 15,000 shots of the Russian vaccine Sputnik V were not loaded on a Qatar Air commercial flight that was scheduled to arrive in the Philippines by 11 p.m. Wednesday.

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Palace spokesman Harry Roque said "logistical challenges" including cold storage requirement and the lack of direct flights from Russia resulted in the delay of the arrival of Sputnik V "trial order."

Vaccine "czar" Carlito Galvez "has taken steps to address these challenges and aims to receive the initial order of the Russian [vaccine] in the month of May instead," Roque said in a statement.

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Galvez later said the Russian jabs may arrive by May 1 if their delivery goes on without further delay.

He added that carriers Philippine Airlines and Cebu Pacific have volunteered to transport the vaccines with a direct flight from Moscow to Manila.

Airline sources said the vaccines are tentatively scheduled to be loaded on board another Qatar Air flight from Moscow to Doha, Qatar with a continuity flight to Manila that will arrive around 11 p.m. Saturday.

The Department of Health said the first batch of Sputnik V jabs would be used for simulation or practice. The remaining 480,000 Sputnik V doses will arrive by the end of April, it said.

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The Philippines has administered at least 1.7 million COVID-19 shots, as of Sunday. It aims to inoculate a third of its population or 50 to 70 million by end of the year to achieve herd immunity.

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The country is expecting an "accelerated delivery" of COVID-19 vaccines beginning next month even as global production of the jabs is seen to stabilize only in June, Galvez earlier said.

-- With reports from Raoul Esperas

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