(Adds comment from U.S. State Department)
By Ben Blanchard
BEIJING, March 31 (Reuters) - China summoned the Philippines ambassador on Monday to lodge a strong complaint over Manila's seeking of international arbitration in a festering territorial dispute over the South China Sea.
The Philippines filed the case against China on Sunday at an arbitration tribunal in The Hague, subjecting Beijing to international legal scrutiny over the waters for the first time.
The United States, a treaty ally of the Philippines, said on Sunday that the right of any state to use dispute resolution mechanisms under the Convention on the Law of the Sea should be respected.
On Monday, the U.S. State Department accused China's coastguard of "harassment" of Philippine vessels and called its attempt on Saturday to block a Philippine resupply mission to the Second Thomas Shoal, a disputed atoll, "a provocative and destabilising action."
Chinese Deputy Foreign Minister Liu Zhenmin told the Philippines' ambassador that Beijing was "extremely dissatisfied and resolutely opposed" to the case Manila had brought to The Hague, repeating that China did not accept it and would not participate.
"The Philippines forcing of international arbitration is not conducive towards resolving the Sino-Philippine dispute over the South China Sea," the Foreign Ministry cited Liu as saying.
The case would not shake China's resolve to protect its sovereignty and territorial integrity, Liu added.
The only way to address the issue was through bilateral talks, he said, repeating another of China's standard lines.
At the weekend, a Philippine vessel delivered food, water and troops to the Second Thomas Shoal, evading two Chinese coastguard ships trying to block its path.
Liu expressed anger at that too, especially as the Philippines took reporters along to what China calls Ren'ai Reef. "China will not tolerate the Philippines' occupation of Ren'ai Reef in any form," he said, calling on the Philippines to stop its "provocative behaviour".
Philippine President Benigno Aquino, speaking to reporters earlier on Monday, said he was not seeking confrontation.
"We are not here to challenge China, to provoke them into any action, but I do believe that they should recognise we have the right to defend our own interests," he said.
State Department spokeswoman Marie Harf said the Philippines was permitted, under the principles of the 2002 Declaration on the Conduct of Parties in the South China Sea, to maintain previously established outposts without interference.
"As a treaty ally of the Republic of the Philippines, the United States urges China to refrain from further provocative behaviour by allowing the Philippines to continue to maintain its presence at Second Thomas Shoal," she told a regular news briefing in Washington.
"We urge China to manage disputes peacefully, to clarify its ambiguous claim in accordance with international law, and to accelerate negotiations with ASEAN on a meaningful code of conduct," she said, referring to the 10-member Association of Southeast Asian Nations.
The latest developments in the dispute come ahead of a visit next month by U.S. President Barack Obama to Asia, including the Philippines. Obama is expected to offer reassurances to regional allies in the face of increasingly assertive Chinese territorial claims.
Chinese Foreign Ministry spokesman Hong Lei said the United States was not a party to the dispute and had said many times it would not take a position.
"We demand that the United States be as good as their word, and do more to benefit peace and stability in the South China Sea, not the opposite," Hong said.
"The Philippine side will certainly face consequences for its provocative actions," he added, without elaborating.
China displays its claims to the South China Sea on official maps with a so-called nine-dash line that stretches deep into the maritime heart of Southeast Asia.
Vietnam, Malaysia, Brunei and Taiwan also have claims to parts of the potentially energy-rich waters. (Reporting by Ben Blanchard; Additional reporting by Manny Mogato in MANILA and David Brunnstrom in WASHINGTON; Editing by Nick Macfie, Alison Williams and Paul Simao)