For more than a decade, China has been using an increasingly aggressive hybrid-warfare strategy to increase its power and influence in the strategically important South China Sea. Countering it will be one of the defining

China is stepping up pressure on the Philippines to concede its sovereign rights in the South China Sea, Manila's Defense Secretary Gilberto Teodoro said on Tuesday after meeting his Australian counterpart in Canberra.

The Philippines has protested China’s baselines around the disputed Scarborough Shoal, as tensions between the two nations build up anew over their competing claims in the South China Sea.

It is the second air-to-sea joint patrol as tensions have escalated around Scarborough, Second Thomas and Sabina shoals.

China's embassy warned the Philippines to cease any "unilateral actions" after Manila brought in two new maritime laws meant to define territory, sea lanes and air routes.