MANILA - China warned Tuesday that the Philippines has "seriously damaged" bilateral ties by asking the United Nations to rule in their favor in a maritime dispute.
Manila at the weekend asked a UN tribunal to declare Beijing's claims over most of the strategically significant South China Sea illegal, submitting nearly 4,000 pages of evidence to back its case.
It argues that the Chinese stance contravenes the UN Convention on the Law of the Sea (UNCLOS), and interferes with the Philippines' sovereign rights to its continental shelf.
"What the Philippine side did seriously damaged bilateral relations with China," Charge d'affaires Sun Xiangyang of the Chinese embassy in Manila said in a statement.
"We find it very hard to understand these moves of the Philippines and we are deeply disturbed by and concerned with the consequence of such moves."
Both countries are signatories to UNCLOS, but Beijing argues that its provisions do not apply to the row.
The embassy statement urged the Philippines to "correct its mistake and come back to the right track of resolving the disputes through bilateral negotiations".
China -- which is vastly more powerful than any of the several countries it has disputes with in the strategically significant waters -- prefers to negotiate with them individually, rather than in international forums.
Apart from China, the Philippines, Brunei, Malaysia, Taiwan and Vietnam also claim parts of the sea.
Sun's comments followed a commentary in People's Daily, the official mouthpiece of the Communist Party, denouncing Manila's move.
"The act of the Philippine side is against the international law and the historical truth as well as against morality and basic rules of international relations," it said.
Manila had "provoked China" by going to "so-called international arbitration, a move that is both illegal and unreasonable" and "an act lacking credibility", it said.
"The Philippines attempted to solicit international sympathy through disguising itself as a small and weak country," the commentary said.
Manila was attempting "to legalize its invasion of Chinese islands through the arbitration", it added.
'PROVOCATIVE AND DESTABILIZING'
The invective from China's state-run media comes as the United States and Japan have rallied to the Philippines' defense.
Tokyo -- which is also embroiled in a bitter territorial row with Beijing -- issued a statement hailing Manila's move, which it said was aimed at "peaceful settlement of disputes on the basis of international law".
"Such an action contributes to the maintenance and enhancement of the international order in the region based on the rule of law," the Japanese foreign ministry said.
Meanwhile Washington, which is a treaty ally of Manila, sharply criticized an attempted Chinese blockade of a Philippine vessel that led to a dramatic two-hour standoff at the weekend.
The move was "a provocative and destabilizing action," US State Department deputy spokeswoman Marie Harf told reporters on Monday.
Harf's statement triggered a stern retort from Chinese foreign ministry spokesman Hong Lei, who maintained Tuesday that "it is without any doubt that the Philippines is the provocateur and troublemaker".
Hong also said that Philippine Ambassador to China Erlinda Basilio was summoned to hear China's strong dissatisfaction and firm opposition to the arbitration attempt.
In the meeting, deputy foreign minister Liu Zhenmin "asked the Philippine side to correct mistakes and return to the right track," Hong said.
Philippine President Benigno Aquino vowed Monday to press ahead with the legal appeal.
"We are not here to challenge China, to provoke them into any action, but I do believe that they should recognize we also have the right to defend our own interests," he told reporters.