The Philippines announced on Saturday that it had suspended its scientific survey of the South China Sea following "harassment and aggressive behavior" by China's coastguard and navy.

Manila and Beijing are involved in a series escalating clashes over the disputed waters of South China Sea. China has claimed almost the entire strategic waterway through which $3 trillion in commerce is moved annually. This overlaps with claims made by the Philippines. Indonesia, Malaysia, and Vietnam.

The Philippine Coast Guard reported that on Friday, two Philippine Bureau of Fisheries (PBF) vessels were attempting to collect sand from Sandy Cay, near the Philippine-occupied Thitu Island, when they encountered three Chinese Coast Guard vessels performing "aggressive maneuvers".

The Philippine Coast Guard, who supported the scientific mission, reported that China sent four small boats to "harass", two rigid-hull inflatable boats used by the Fisheries Bureau to transport personnel to Sandy Cay.

It also said that a Chinese navy helicopter hovered over the craft at an "unsafe height".

The Philippine Coast Guard announced that survey operations had been suspended "due to the harassment of the Chinese maritime forces and their disregard for safety".

The Chinese Embassy in Manila didn't immediately respond to our request for comment.

Manila and Beijing reached an agreement on January 16 during a round-table discussion to find common ground in their disputes over the South China Sea and to explore ways of cooperating.

In 2016, an international arbitration tribunal found that China's claims based on historical maps were not backed by international law. Beijing did not accept this ruling.

(source: Reuters)