The patrol comes less than a week after Philippine President Ferdinand Marcos Jnr signed the Maritime Zones Act and Archipelagic Sea Lanes Act, embedding Manila’s claims to the South China Sea in domestic law. The US expressed its support for the Philippine legislation, saying other countries had passed similar laws.

China has held sea and air combat drills at disputed Scarborough Shoal, an uninhabited area of reefs and rocks it had seized from the Philippines in the South China Sea.

China declared its maritime baselines around Scarborough Shoal after the Philippines passed laws defining its maritime zones and sea lanes last week.

The Philippines' foreign ministry summoned the Chinese ambassador on Wednesday, November 13, to protest against Beijing's establishment of baseline coordinates around the disputed Scarborough Shoal in the South China Sea,

A protest was filed in relation to China’s action, the Philippines’ Department of Foreign Affairs ... said it delimited the baselines of the territorial sea adjacent to Scarborough Shoal — which it calls Huangyan Dao — saying it’s a “natural ...

The ongoing territorial disputes in the South China Sea, China conducted intensive sea and air combat drills near the contentious Scarborough Shoal on Wednesday. This area—an expanse of reefs and rocks west of the Philippines’ Luzon Island—has been a persistent flashpoint in China-Philippines relations since China seized control of the shoal in 2012.

The Philippines has explicitly labeled China's baseline declarations around Scarborough Shoal (Bajo de Masinloc) as illegal under international law — a direct pushback against Beijing after it aired its fury over Manila's new maritime zones law.