Philippine President Ferdinand Marcos Jr. spent the first 15 months of his term working with the U.S. and its allies to counter China’s incursions in the South China Sea. Now, his government is taking the fight more directly to Beijing in a move that could force the U.S. to make some tough choices.

Marcos this week ordered a "special operation” in which his coast guard removed a barrier installed by China at the entrance of the Scarborough Shoal, a chain of reefs and rocks the two sides claim as their own. Footage posted by the Philippine coast guard shows a knife-wielding man in scuba gear slicing through a rope connecting buoys that they say threatened fishers and was "a clear violation of international law.”

The move, the coast guard says, is part of a strategy developed over several months to retake the area — a traditional fishing ground for the Philippines and its neighbors — which Beijing has effectively controlled since 2012 after a weekslong standoff with Manila. China Foreign Ministry spokesman Wang Wenbin quickly warned the Philippines "not to make provocations or seek troubles.”