Beijing has warned Manila against any moves that may complicate or escalate tensions between the two nations, in response to the Philippines' seeking United Nations arbitration over its territorial claims.

China-Philippine ties were frayed last April after a Philippine warship first prompted a serious impasse in the waters off China's Huangyan Island in the South China Sea.

Observers said Manila's high-profile lawsuit was just "political posturing" and it has shown little willingness for one-on-one negotiations on relevant disputes.

Philippine Foreign Secretary Albert del Rosario said on Tuesday that the Philippines government has taken the South China Sea disputes to an Arbitral Tribunal under the United Nations Convention on the Law of the Sea.

Foreign Ministry spokesman Hong Lei told reporters on Wednesday that Beijing supports bilateral negotiation with the countries involved, as previously agreed by China and members of the Association of Southeast Asian Nations.

"As stated in the Declaration on the Conduct of Parties in the South China Sea, China and members of ASEAN have reached a consensus on this," said Hong, stressing that all countries signing the declaration should adhere to their commitments.

Yang Baoyun, an expert on Southeast Asian studies at Peking University, said that the international court will take the case seriously on the precondition that both parties approve the case, and Manila knows that Beijing is unlikely to respond.

Manila first started to make claims to China's Huangyan Island in the 1990s.

On April 10, a Philippine gunboat entered the waters off the island and attempted to detain Chinese fishermen, who were later rescued by two Chinese patrol ships.

Beijing has since beefed up regular patrols of the waters, and del Rosario on Monday admitted that the island is under China's control, according to local media reports.

Despite its claim, Manila is now being accused of using the island issue as a political gesture to attract more attention, analysts said. Yang said, "As for its persistent resorting to the international tribunal, the Philippines is seeking to gain more international sympathy while trying to appear a victim."

In New York on Tuesday, UN Secretary-General Ban Ki-moon told reporters that "all these issues should be resolved by the parties concerned".

It was important for the countries in the region to resolve disputes "through dialogue in a peaceful and amicable way", Ban added.

Meanwhile, Hong, the Foreign Ministry spokesman, stressed that the origin and essence of relevant South China Sea disputes between Beijing and Manila lies in the Philippines' illegal occupation of some islets and reefs of China's Nansha Islands in the South China Sea, which China has consistently opposed..

He said China has shown "the utmost goodwill and sincerity" in addressing disputes with the Philippines through bilateral consultations and negotiations.

Xinhua and AP contributed to this story.

Contact the writer at zhangyunbi@chinadaily.com.cn