MANILA - President Rodrigo Duterte on Monday hailed China as the first country to help the Philippines in the fight against COVID-19, saying in his last State of the Nation Address (SONA) that he is indebted to Asia's largest economy.

Duterte said Chinese President Xi Jinping was the first global leader he called to seek help for the acquisition of COVID-19 vaccines.

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"When the pandemic struck, the first country I called for help is China," he said an hour and a half into his speech.

"Sabi ko, President, we have no vaccination program here... We were not able to invent one. We might have a hard time," Duterte said.

"He (Xi) said it's okay, we will send [vaccines to] you," he said, noting that China donated around 1.5 million COVID-19 jabs to the Philippines.

While Chinese pharmaceutical giant Sinovac donated some 1 million jabs to the country, the Philippines paid for 16 million other vaccines from the company, based on tracking by the ABS-CBN Investigative and Research Group.

Duterte admitted that he was indebted to China, which has been militarizing several areas within the Philippines' exclusive economic zone in the West Philippine Sea.

"Ako, lalo na kaming mga Bisaya, mabigat sa amin yan. 'Yung utang na loob, mabigat talaga yan," he said.

(To me, especially to Visayans, we take it seriously. We take our debts of gratitude seriously.)

"Kapag may utang na loob ako sa iyo (If I have a debt of gratitude to you), you will be sure I will be your true friend and die for you," he said.

Duterte was inoculated with Chinese-made vaccine Sinopharm even before the pharmaceutical company secured an authorization from the Philippine Food and Drug Administration to use the vaccine for emergency purposes.

In 2016, an international tribunal awarded an arbitral victory to the Philippines and invalidated China's sweeping 9-dash line claim in the South China Sea.

Duterte has not enforced the decision, saying Philippine troops are no match for China's military.

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