Philippine President Benigno Aquino warned his country's neighbours on Monday they should fear Beijing's growing aggressiveness over its claims in the South China Sea.
Aquino stressed China's territorial claims spanned a huge area and were getting "closer and closer" to the Philippine archipelago.
"They claim this entire body of water practically. Look at what is excluded and what they are claiming," Aquino told reporters as he pointed to a map of the area. "So how can the others not be fearful of what is transpiring?"
Aquino's comments came shortly after his government said it would raise an increasingly tense dispute with China over the Scarborough Shoal at a high-level bilateral meeting with the US next week.
Manila and Beijing have been locked in a standoff over Scarborough, a group of islands in the South China Sea, since Chinese vessels blocked Philippine attempts to arrest eight Chinese fishing boats' crews earlier this month.
Aquino said Scarborough was within the Philippines' internationally recognised exclusive economic zone and questioned China's historical basis for its claims.
"Its like (their claims) are getting closer and closer" to shore, he said.
The shoal is about 230 kilometres (140 miles) from the Philippines' main island of Luzon, while the nearest Chinese land mass is Hainan province 1,200 kilometres to the northwest, according to Philippine naval maps.
With China ratcheting up the pressure, Manila said earlier Monday the Scarborough issue would be formally raised in talks between Foreign Secretary Alberto del Rosario and Defence Secretary Voltaire Gazmin and their US counterparts Hillary Clinton and Leon Panetta in Washington next week.
The two nations are bound by a mutual defence pact in which the United States has pledged to come to the aid of its weaker ally if it faces military aggression.
Manila's move could further anger China, which has insisted the United States should have no role in the dispute.
China claims almost the entire South China Sea and is also locked in disputes with Association of Southeast Asian Nations (ASEAN) countries Brunei, Malaysia and Vietnam, as well as its rival Taiwan.
The Philippines had earlier called on ASEAN countries to take a common stand against Beijing over the South China Sea, a call that has caused differences within the bloc fearful of antagonising the region's most powerful nation.
The Global Times, a newspaper run by China's ruling Communist Party, warned in an editorial at the weekend of a potential "small-scale war" to end the Scarborough Shoal standoff.
"Once the war erupts, China must take resolute action to deliver a clear message to the outside world it does not want a war, but definitely has no fear of it," the editorial said.