Increasingly assertive about these claims, China has also engaged in maritime disputes with Brunei, Malaysia, Taiwan and Vietnam in different parts of the South China Sea, and with Japan over islands in the East China Sea.

Image President Benigno S. Aquino III Credit... Seth Wenig/Associated Press

The Chinese have sought one-on-one talks with the Philippines to resolve the dispute, but Mr. Aquino has rejected that approach — there are at least four countries with overlapping claims in the Spratlys alone, he said, so it makes no sense for two of the countries to negotiate with each other.

“We cannot agree to bilateral talks to solve the problem, because we think the problem is multilateral,” he said. “A multilateral problem has to be settled multilaterally.”

He described the relationship with China as confusing at times. While trade between the two nations continues to grow, he said, a travel advisory is in force in China discouraging visits to the Philippines. Other mixed messages recur as well. “There was a time when they were stopping our exports of bananas,” Mr. Aquino said.

“At the end of the day, it goes from hot to cold, sometimes they’re very conciliatory, sometimes they make very provocative statements,” he said. “We will confess we don’t understand some of the messages sometimes. We’re not sure.”