China is "strongly dissatisfied and firmly opposed" to the United States, Japan and the Republic of Korea interfering in its internal affairs and sowing discord between China and its neighbors, Foreign Ministry spokesman Wang Wenbin said.

Wang made the remarks on Monday, after leaders of the US, Japan, and the ROK met at Camp David in Maryland and issued a joint statement attacking China over the South China Sea issue and the Taiwan question.

The allies have breached basic norms guiding international relations and China has made solemn demarches to the parties involved, Wang told a news conference.

Noting the US has said its trilateral partnership with Japan and the ROK is not against anyone, Wang urged the US to honor its words with actions and stop smearing China and hurting China's interests.

Also, Washington, which has "dominated" efforts to stoke division and revive Cold War mentality in the Asia-Pacific by forming cliques such as AUKUS and Quad, should cease creating confrontation and undermining regional peace, Wang said.

"The Asia-Pacific is a land for peaceful development and should not become a boxing ring for great power rivalry, even less a battlefield for cold or hot war," Wang said.

"We urge relevant countries not to … try replicating bloc confrontation in the Asia-Pacific, and not to pursue selfish interest at the expense of other countries' strategic security interests and the wellbeing of people in the region."

Speaking of the Taiwan question, Wang said China strives for peaceful reunification with the greatest sincerity and utmost efforts, but will never allow interference in its internal affairs under the pretext of peace.

The greatest threat to peace across the Taiwan Strait is "Taiwan independence" activities and foreign connivance and support to them, Wang said.

"If relevant countries do care about cross-Strait peace and stability, they should follow the one-China principle and stop conniving or supporting 'Taiwan independence' separatists or their separatist activities," the spokesman said, adding that no one should underestimate China's will to safeguard its sovereignty and territorial integrity.

Rebuking accusations over maritime issues made by the US, Japan and the ROK in their joint statement, Wang said China has indisputable sovereignty over the South China Sea islands and their adjacent waters.

"It is reasonable and lawful for China to carry out construction on its own territory and for the Chinese coast guard vessels to carry out law enforcement in waters under China's jurisdiction," Wang said.

Also, as a signatory to the United Nations Convention on the Law of the Sea, China has always faithfully followed the convention and other international laws, and does not accept or recognize the illegal award on the South China Sea arbitration, Wang said.

In recent years, the US has "done all it can" to interfere in the South China Sea issue, Wang said.

China will continue to firmly safeguard its sovereignty and security interests, and work with member states of the Association of Southeast Asian Nations to implement the Declaration on the Conduct of Parties in the South China Sea, Wang said.