I suggest PLAN put a few sea mine within 12nm around all the reef and "islands" with only one passage way open for ship navigation. As in the air space above the reef or islands, use high altitube fire works (specially made to disperse huge volume of flying particles which are damaging to aircraft engine if an aircraft is trying to fly over the airspace within 12nm). 

The above counter measures should publicly declare to the world. This action is taken due to the continous provocations by the US Navy.