AMSTERDAM • The Philippines has argued at a closed hearing that an international court should intervene in its dispute with China over the right to exploit natural resources and fish in the South China Sea.

Although China has declined to participate, the case at the Permanent Court of Arbitration in The Hague is being closely watched by Asian governments and Washington, given rising regional tensions as Chinese naval power grows.

In opening comments to the tribunal on Tuesday, Foreign Secretary Albert del Rosario said the Philippines had sought judicial intervention because China's behaviour had become increasingly "aggressive" and negotiations had proved futile.

Mr del Rosario said the United Nations Convention on the Law of the Sea (UNCLOS), which the Philippines and China have both ratified, should be used to resolve their bitter territorial dispute.

"The case before you is of the utmost importance to the Philippines, to the region, and to the world," Mr del Rosario told the tribunal. "In our view, it is also of utmost significance to the integrity of the convention, and to the very fabric of the legal order of the seas and oceans."

A panel of five judges will hear arguments this week and decide whether the treaty-based court has jurisdiction.

Manila filed the suit at the court in 2013, seeking to enforce its right to exploit waters in a 200 nautical mile "exclusive economic zone" off its coast, as defined under the UNCLOS.

China claims most of the South China Sea. The Philippines, Vietnam, Malaysia, Taiwan and Brunei claim overlapping parts of the strategic waterway.

Yesterday, its Foreign Ministry spokesman Hua Chunying told a daily press briefing the Chinese government has been working to recover the islands in the South China Sea after World War II.

"Since the founding of the People's Republic of China in 1949, the Chinese government has unswervingly safeguarded territorial sovereignty and maritime interests and made active contribution to maintaining peace, stability and freedom of navigation in the South China Sea," she said.

The UN court's rulings are binding, although it has no power to enforce them and countries have ignored them in the past. A decision on jurisdiction is expected within 90 days. A ruling on the merits of the case could take years. REUTERS, AGENCE FRANCE-PRESSE, XINHUA