China has lodged stern protests with the United States after US Secretary of State Marco Rubio expressed opposition to the establishment of a national nature reserve at Huangyan Island, urging Washington to stop making trouble and sowing discord in the South China Sea.

Addressing a regular news briefing on Monday, Foreign Ministry spokesman Lin Jian said Huangyan Island is China's inherent territory and the establishment falls fully within China's sovereignty, which is lawful, reasonable, and brooks no interference.

He accused Washington of meddling in South China Sea affairs despite not being a party to the disputes, saying the US frequently stirs up tensions by drawing in other countries and serves as the real troublemaker in the South China Sea.

He said China will continue working with ASEAN countries to fully implement the Declaration on the Conduct of Parties in the South China Sea and advance negotiations on the Code of Conduct in the South China Sea.