China's military on Thursday vowed to defend the country's territory amid a stand-off with the Philippines in the disputed South China Sea, the official Xinhua news agency said.

China is locked in a maritime dispute with the Philippines over the Scarborough Shoal in the South China Sea, which is considered a potential Asian flashpoint due to the overlapping claims of several nations.

"China's armed forces bear the responsibility for the task of defending the nation's territorial sovereignty and safeguarding maritime rights and interests," defence ministry spokesman Geng Yansheng was quoted as saying.

China claims all of the South China Sea as a historic part of its territory, even waters close to the coasts of the Philippines and other Southeast Asian countries.

Geng added the military would cooperate with Chinese government bodies handling fishery and maritime affairs to safeguard the country's rights, Xinhua said, but gave no further details.

The Philippines said Thursday it would seek more US military help during top-level talks next week, despite China's warning not to "internationalise" the tense territorial dispute.

Foreign Secretary Albert del Rosario said the Philippines was looking to the United States to help it achieve a "credible" defence system, and wanted to extract maximum benefits from a mutual defence treaty between the allies.

The United States and the Philippines are now holding military exercises though officials of both countries deny a link to the dispute with China.

The Philippines has complained over the past two years that China has become increasingly aggressive in staking its claim to the waters, with tensions spiking over the Scarborough Shoal standoff.

China itself is currently holding naval exercises with Russia off the Chinese coast which included live-fire drills on Thursday, state media said.

The exercises are the first ever dedicated naval drills between the two countries.

China plans more military exercises with Russia and central Asian countries belonging to a regional grouping which have been scheduled for June in Tajikistan, Geng said.

He added that China's recent tests of its first aircraft carrier had no relationship to the "current regional situation".

That vessel, a refitted former Soviet carrier called the Varyag, underwent its second sea trial in November last year.