The United States has accused China of 'destabilising' Asian region over the South China Sea claim.
US Defence Secretary Chuck Hagel said China's action threatened the region's long-term progress, adding that the US would 'not look the other way' when nations ignored international rules.
According to the BBC, Hagel was speaking at a three-day summit, the Shangri-La Dialogue in Singapore, that involves the US and Southeast Asian countries.
The forum comes amid growing tensions between China, Vietnam and the Philippines, with Japan-China ties also strained over disputed islands in the East China Sea, the report said.
Hagel said that in recent months, China has undertaken destabilising, unilateral actions asserting its claims in the South China Sea.
He added that the US firmly oppose any nation's use of intimidation, coercion, or the threat of force to assert these claims, making a reference to the way China has claimed territorial rights over areas of the South China Sea close to Japan, the Philippines and Vietnam, the report added.