It may be too late for any "formal US strategy" to stop or slow China's land reclamation in the South China Sea, according to a Philippine defence analyst.
"The option of slowing or stopping these reclamation activities depends solely now on China. It depends on China's appreciation of the situation," Mr Rommel Banlaoi, head of the Centre for Intelligence and National Security Studies, told The Straits Times on Friday.
He was responding to a report that leading US senators had expressed alarm at the scale and speed of China's land reclamation in the South China Sea and said a formal US strategy was needed to slow or stop the work.
China has already reclaimed 60 hectares in four Philippine-claimed atolls and reefs in the Spratly chain of islands alone, already altering their physical features and changing the status quo in the South China Sea, Representative Francisco Acedillo, a former military pilot, said earlier.
China has built artificial islands in five reefs in the Spratly - Gaven, Johnson South, Cuarteron, Hughes and Fiery Cross - and it has begun dredging works on two more reefs, Mischief and Subi.
Mr Acedillo said these islands would serve as "forward operating bases" that could sustain round-the-clock naval and air patrols, "virtually allowing China to stake their claim to at least 80 per cent or even the entire South China Sea".
Legal analyst Harry Roque, head of the University of the Philippines' Law Centre Institute of International Legal Studies, said what Washington can do effectively now is to deny China's new islands "territorial sea".
He said the US must declare that these islands, being man-made, are not entitled to 200 nautical miles of "exclusive economic zone".
"Otherwise, the maritime zones that (the islands) may create may be a hindrance to freedom of navigation," said Prof Roque.
The Philippines' case before the United Nations challenging China's claims to nearly all the South China Sea is based largely on land features.
Citing the UN Convention on the Law of the Seas, Manila has argued that the rocky outcrops that China has now transformed into artificial islands are not entitled to any maritime territories as they are largely submerged.
That argument now stands on shaky ground, as the reefs have now been transformed into islands with a combined area equivalent to a small city.