China has indisputable sovereignty over Nansha Qundao, including Ren'ai Jiao and their adjacent waters, as well as the Diaoyu Islands and their affiliated islets, Foreign Ministry spokesperson Mao Ning said on Friday during a regular press briefing.

She made the remarks in response to U.S. President Joe Biden's commitment to "deepening maritime and security ties" with Japan and the Philippines.

Japan, the Philippines and the U.S. held a summit on Thursday and voiced oppositions to China's activities in the South China Sea and East China Sea in their joint vision statement.

China's activities in the East China Sea and South China Sea are in full compliance with international law, Mao said. 

China is committed to safeguarding its territorial sovereignty and maritime rights and interests and maintaining the peace and stability of the South China Sea, she added. 

Mao said China resolutely opposes relevant countries infringing on China's sovereignty and development interests in the name of freedom of navigation and overflight.

The so-called award of the South China Sea arbitration is illegal and void, the spokesperson noted, adding that China's territorial sovereignty and maritime interests are not affected by the award in any circumstances.

Emboldened by the support of non-regional countries, certain countries have continued to take provocative actions at sea, thus raising the tension of the situation, Mao said. It is outrageous that certain non-regional countries are fanning the flames and provoking confrontation, she added.

The U.S. clings to the Cold War mentality and threatens other countries with a bilateral treaty of alliance, which seriously violates the United Nations Charter and undermines regional stability, she said.

She also reiterated China's commitment to dealing with maritime issues with countries directly concerned through dialogue and consultation while opposing the interference of non-regional countries to stir up trouble and escalate the situation.