"The United States is concerned by reports of China's repeated provocative actions aimed at the offshore oil and gas development of other claimant states," the US State Department said in an emailed statement on Saturday.

"In this instance, (China) should cease its bullying behavior and refrain from engaging in this type of provocative and destabilizing activity," it said.

China's actions threaten regional energy security and undermine the free and open Indo-Pacific energy market, the State Department added.