The assertion of Philippine sovereignty over the islands in the South China Sea signifies an apparent change of tack likely to anger China.
Philippine President Rodrigo Duterte on Thursday ordered troops to occupy uninhabited islands and shoals his country claims in the disputed South China Sea.
Duterte's comments are unlikely to sit well with China, which lays claim to almost all the South China Sea, especially as it comes amid a fast-warming relationship in recent months.
"The unoccupied, which are ours, let's live on it," Duterte told reporters during a visit to a military base in Palawan, near the disputed waters.
"It looks like everyone is making a grab for the islands there. So we better live on those that are still unoccupied. What's ours now, we claim it and make a strong point from there."
The firebrand leader also said he might visit the island of Thitu, the largest of the Philippine-controlled islands in the Spratly archipelago, and build a barracks for servicemen operating in the area.
Thitu is close to Subi Reef, one of seven man-made islands in the Spratlys that China is accused of developing as military outposts.
China, Malaysia, the Philippines, Taiwan, Brunei and Vietnam contest all or parts of the South China Sea. This has led to confrontations between China and some of its neighbours over the strategic trade route.
Duterte's comments came as US President Donald Trump and Chinese President Xi Jinping held their first meeting in Florida on Thursday.
The US State Department declined comment on Duterte's remarks, but has in the past urged rival South China Sea claimants to lower tensions and resolve differences in accordance with international law.
Duterte announced his "separation" from the United States in October, declaring he had realigned with China as the two agreed to resolve their South China Sea dispute through talks.
His efforts to engage China, months after a tribunal in the Hague ruled Beijing did not have historic rights to the South China Sea, in themselves marked a reversal in foreign policy.
The Philippines occupies nine "features", or islands and reefs, in the South China Sea, including a World War II-vintage transport ship which ran aground on Second Thomas Shoal in the late 1990s.
Last month, Defence Minister Delfin Lorenzana said the Philippines would strengthen its facilities in the Spratlys by building a new port and paving an existing rough airstrip.