The Philippines will challenge China's territorial claims to the South China Sea at an international tribunal.
According to the BBC, Foreign Secretary Albert del Rosario said the move came after Manila had exhausted all political and diplomatic avenues into the matter.
The tribunal of the UN Convention on the Law of the Sea will arbitrate whether the presence of China's activists in the South China Sea violates the Philippine's sovereignty, Reuters reported.
GlobalPost's Benjamin Carlson, reporting in Hong Kong, says the Philippines seems emboldened by the United States' implicit support, and has become remarkably assertive in its claims against China.
"It will be interesting to see how it plays out, given that, in public, Chinese diplomats pay lip service to the international law, but if the UN were to rule against China, it's very hard to imagine them abiding by the ruling," Carlson said. "To be honest, China is similar to the US in that respect."
Though several countries claim parts of the South China Sea, China claims virtually all of the sea, the Guardian reported. Last year, China confronted Filipino ships in a standoff over the Scarborough shoal.
However, even if the tribunal orders China to respect the Phillipines claims, China could always choose to ignore it. The BBC reported that the Philippines' move may be dangerous as the country is dependent on China economically.
There has been no reaction from Beijing over the request for a tribunal.
Benjamin Carlson contributed reporting from Hong Kong. Follow him on Twitter @bfcarlson.