Bangkok: Australian military personnel, including special force commandos, are taking part in three-nation war games near the flashpoint waters of the South China Sea that have riled China.
China's state newsagency Xinhua warned "outsiders" against interfering in South China Sea territorial disputes as the 12-day exercises got underway in the Philippines.
Xinhua warned that tensions in the region have risen to a "tipping point" and "some specific nations take delight in sowing seeds of discord between China and rival claimants, and boosting their military presences and patrols to thwart China in the name of safeguarding the freedom of navigation." 
"However, a provocation so fear-mongering and untimely as such is likely to boomerang on the initiators," Xinhua said.
Australia has sent 86 military personnel, including 30 commandos from the 2nd Commando Regiment, to the annual war games called Balikatan that are hosted by the United States and the Philippines.
An RAAF AP-3C Orion maritime patrol aircraft and crew will also participate.
In a show of force amid concern about China's growing assertiveness in the region three Japanese war ships also docked at Subic Bay, the Philippines' strategic port, the first to include a Japanese submarine in 15 years.
Japanese defence officials will attend the exercises only as observers but the US Defence Department announced last week that Washington is in talks with Tokyo about Japan participating in future joint drills.
Wing Commander Bill Talbot, commander of the Australian contingent, said Australia's involvement confirms Canberra's "friendship with and support to the Philippines while maintaining good interoperability with US forces assigned to US Pacific Command."
Australia last year donated two heavy landing aircraft to the Philippine Navy which has one of the weakest militaries in the region.
Australian personnel will be involved in a mock amphibious landing exercise as well as doing humanitarian work.
US Defence Secretary Ash Carter is to fly to the Philippines next week, reinforcing a newly signed defence pact with Manila that will see US troops regularly deployed to five Philippine bases. 
Mr Carter will observe live-firing from a US war ship of high mobility rockets that the US deployed for Balikatan, which means "shoulder to shoulder" in the Philippine language.
The rockets are designed to shoot down aircraft.
China, which lays claim to almost all of the South China Sea, has been building airstrips and structures, including radar systems, on reefs and islands in the waterways through which US$5 trillion of trade passes each year, sparking international concern.
The US has responded by conducting what it calls "freedom of navigation" patrols, sailing ships near disputed islands to underscore the right to freely navigate the seas.
Adding to tensions, a decision is expected soon from a UN-backed tribunal on a legal challenge by the Philippines to China's territorial claims.
Balikatan has evolved from past counter-terrorism manoeuvers against Islamic extremist groups in the southern Philippines to simulations of retaking and protecting territory as disputes with China have escalated in recent years.
This is the third time Australian forces have participated in the exercises.
Lieutenant-General John Toolan, commander of US Marine Corps forces in the Pacific, told reporters in Manila that Balikatan would help US allies improve maritime security and maintain regional stability.
"Our alliance is strong. The United States is committed to this relationship and these are not empty words???peace in south-east Asia depends on our cooperation," he said.
Almost 10,000 military personnel will be taking part in the exercises which are centred around air bases just 230 kilometres from disputed waters.
Other claimants to parts of the South China Seas are the Philippines, Taiwan, Malaysia, Brunei and Vietnam.
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