Chinese military buildup in SCS challenges Xi's statement: US

China's military buildup in its manmade island in the disputed South China Sea calls into question the country's willingness to abide by President Xi Jinping's statement about the area, the US has said.

"This type of potentially dual-use construction activity has raised tensions in the region. It also calls into question China's willingness to abide by President Xi's statement last September that China does not intend to militarise its outposts in the Spratly," State Department spokesperson Elizabeth Trudeau told reporters on Tuesday.

"Such actions undermine regional confidence that China's willing to resolve contested matters in a non-coercive manner," she said.

Trudeau was responding to a question on a latest report in which a Washington-based think tank using satellite pictures had said that China was having military buildup at its manmade island in the disputed South China Sea.

"We reiterate, as we have in the past, our call for all claimants to halt land reclamation in disputed areas in further development of new facilities and new militarisation of their outposts, and instead to utilise the opportunity presented by the July 12th arbitral tribunal's decision to reach an understanding on appropriate behaviour and activities in disputed areas," Trudeau said.

According to the Centre for Strategic International Studies, latest satellite photograph shows that China has built aircraft hangars on one of the disputed islands.

"It certainly calls into question China's willingness to abide by President Xi's statement," Trudeau said.

China claims sovereignty over almost all of SCS based on historic rights, including reefs and rocks in the sea as well as hundreds of miles from Chinese shores.

Besides the Philippines, Vietnam, Malaysia, Brunei and Taiwan have counter claims over the area.

China also opposes US naval and air patrols over the area to assert freedom of navigation.