The United States is pledging $40 million in military aid to help the Philippines protect its territorial waters.
Secretary of State John Kerry made the announcement during his recent visit to the Asian nation. It comes amid rising tensions with China over territory in the South China Sea.
Beijing recently issued a unilateral declaration of an air defense zone in the East China Sea that sparked tensions with Japan.
At a press conference Tuesday with Philippine Foreign Secretary Albert del Rosario, Kerry said the United States neither recognizes nor accepts China's declaration.
"The zone should not be implemented and China should refrain from taking similar unilateral actions elsewhere in the region, particularly over the South China Sea," he said, countering Chinese hints of establishing a similar zone in the South China Sea.
Del Rosario said such a claim would present a problem for the Philippines. Kerry assured him the United States "remains firmly committed to the security of the Philippines and of that region."
Part of the $40 billion aid will be used to strengthen Filipino counter-terrorism efforts against local al Qaeda-linked terror cells.
Kerry said the announcement is part of the Obama administration's decision to refocus on Asia.