WASHINGTON • The United States has seen Chinese activity around a reef that China seized from the Philippines nearly four years ago, which could be a precursor to more land reclamation in the disputed South China Sea, said US Navy chief Admiral John Richardson.
He expressed concern that an international court ruling expected in the coming weeks on a case brought by the Philippines against China over its South China Sea claims could be a trigger for Beijing to declare an exclusion zone in the busy trade route.
Adm Richardson told Reuters on Thursday that the US was weighing responses to such a move.
China claims most of the South China Sea, through which more than US$5 trillion (S$6.8 trillion) in global trade passes every year. Vietnam, Malaysia, Brunei, the Philippines and Taiwan have rival claims.
Adm Richardson said the US military had seen Chinese activity around Scarborough Shoal in the northern part of the Spratly archipelago, about 200km west of the Philippine base of Subic Bay.
"I think we see some surface ship activity and those sorts of things - survey type of activity - going on. That is an area of concern... a next possible area of reclamation," he said.
CONCERNS ON REEF ACTIVITIES
I think we see some surface ship activity and those sorts of things - survey type of activity - going on. That is an area of concern... a next possible area of reclamation.
ADMIRAL JOHN RICHARDSON, US Navy chief.
Adm Richardson said it was unclear if the activity near the reef, which China seized in 2012, was related to the pending arbitration decision.
Asked about Adm Richardson's statement, Mr Lu Kang, a spokesman for China's Ministry of Foreign Affairs, said it was hypocritical for the US to criticise China for militarising the region when it carries out its own naval patrols there.
"This is really laughable and preposterous," he said.
The Philippine foreign ministry said it had yet to receive a report about Chinese activity in Scarborough Shoal.
A Philippine military official told reporters: "China already has de facto control over the shoal since 2012 and they always have two to three coastguard ships there.
"We are also monitoring their activities and movements."
Adm Richardson said China's pursuit of South China Sea territory, which has included massive land reclamation to create artificial islands elsewhere in the Spratlys, threatened to reverse decades of open access and introduce new "rules" that required countries to obtain permission before transiting those waters.
He said that was a worry, given that 30 per cent of the world's trade passes through the region.
Asked whether China could respond to the ruling by the court of arbitration in The Hague by declaring an air defence identification zone (ADIZ) as it did in the East China Sea in 2013, Adm Richardson said: "It's definitely a concern. We will just have to see what happens."
Adm Richardson said he was struck by how China's increasing militarisation of the South China Sea had increased the willingness of other countries in the region to work together.
India and Japan have joined the US Navy in the Malabar naval exercise since 2014, and were due to take part again this year in an even more complex exercise that will take place in an area close to the East and South China Seas.
South Korea, Japan and the US were also working together more closely than ever before, he said.
"We have to be sophisticated in how we approach this so that we don't force any of our partners into an uncomfortable position where they have to make trade-offs that are not in their best interest," Adm Richardson said.
"We would hope to have an approach that would... include us as a primary partner but not necessarily to the exclusion of other partners in the region."