The Philippine defense secretary says his country and its allies would take measures to counter any attempt by China to impose an air defense zone or restrict freedom of flights over the South China Sea.

Philippine and U.S. Navy SEALs secured a gas and oil platform in the South China Sea in the latest joint combined exchange training between the two special operations units near the disputed waters last week.

China has accused the Philippines of polluting the environment after it released footage it said showed troops burning rubbish at a disputed reef in the South China Sea. The video, published on social media by state broadcaster CGTN on Saturday,

China has monitored a Philippine civilian vessel supplying a warship at the contested Second Thomas Shoal. China urges cooperation from the Philippines and to cease exaggerating tensions. The Philippine embassy in Beijing has yet to comment on the situation.

Indonesia is one of the founding members of ASEAN and long served as its de facto leader, playing a crucial role in mediating regional crises. Analysts warned that its leadership in the group on the South China Sea issue would wane if it stopped championing international legal norms.

The Philippines and Japan pledged to enhance their defense alliance through training exercises, logistical activities, equipment transfers and intelligence sharing on Monday amid China’s assertive moves in the South China Sea.

China said it monitored a Philippine civilian boat delivering daily provisions to the "illegally grounded" warship at the disputed Second Thomas Shoal on Wednesday, a statement from the coast guard said.

Philippines officials accused a Chinese government-owned broadcaster of spreading misleading information and propaganda following its claim that a Philippine vessel was intentionally polluting the waters of the South China Sea,