Chinese Ambassador to the Philippines Huang Xilian urged on Friday the Duterte administration to "stay alert" as he accused "certain countries" of trying to sow discord by taking advantage of the differences between China and the Philippines.

Huang made the statement during his attendace at the Vaccine Summit of the Philippine International Chamber of Commerce and the Philippine Chamber of Commerce and Industry.

"The pandemic is a test for friendship. Certain countries, while looking on Philippines’ anxiety of vaccine need with indifference, tried to sow discord by taking advantage of the differences between China and the Philippines. We should stay alert," he said.

"Tougher the time is, wider our eyes open. We would eventually know who the real friends and reliable partners are," Huang said.

The envoy did not mention those countries trying to create discord between Beijing and Manila.

The two countries are engaged in a maritime dispute particularly in the West Philippine Sea.

Despite repeated demand from the Philippines and subject of diplomatic protests, Chinese vessels continue to swarm in Julian Felipe Reef, an area within the Philippine exclusive economic zone.

China has been claiming almost the entire South China Sea despite a 2016 arbitral ruling invalidating Beijing's historic and sovereign claim in the area through its nine-dash line.

The European Union and the United States, among others, have been calling on China to honor and respect the arbitral ruling and abide the United Nations Convention on the Law of the Sea.

Huang noted China's donation of one million doses of Sinovac COVID-19 vaccine to the Philippines.

He also said that Beijing is prioritizing vaccine exports to Manila.

"Certain vaccine-producing countries hoard large amounts of vaccines far beyond their real needs. They also prohibit the export of raw materials for vaccine production, resulting in serious shortage of vaccines in developing countries. Vaccine nationalism, contrary to international fairness and justice, undermines international community’s hard work to fight against the pandemic," he said.

Huang said Chinese vaccines have become the major source of Philippine vaccination.

Some 3.5 million doses of Chinese vaccines have arrived in the Philippines and another 2 million procured doses will arrive in May, he added. Celerina Monte/DMS