China rebuts Philippine South China Sea claims with legal critique

China reiterated that the Philippines' territorial claims in the South China Sea lack both historical and legal basis and pose a serious threat to regional stability and the international order, according to a report released Wednesday by the Ministry of Natural Resources.

The report comes amid rising tensions fueled by recent Philippine-Japanese activities, and against the backdrop of the 10th anniversary of China's rejection of an arbitration ruling that Manila continues to cite in support of its maritime claims.

While China has previously laid out evidence of its sovereignty and refuted Philippine claims in various official documents, the new paper is described as the first comprehensive assessment of the legal validity of Manila's territorial assertions in the South China Sea.

Titled Historical and Legal Critique of the Philippines' Territorial Claims in the South China Sea, the report is the latest in a series of works published by the China Institute for Marine Affairs (CIMA), a think tank under the Ministry of Natural Resources.

The report argues that the Philippines' historical borders have never included any of China's South China Sea islands (Nanhai Zhudao in Chinese). It says Manila only began asserting claims over parts of China's Nansha Islands and Huangyan Dao, starting in the 1970s.

It rejects each of the legal and historical grounds cited by the Philippines, including geographical proximity and historical maps, arguing that they are either unsupported by international law or do not constitute valid evidence.

Citing the international legal principle of estoppel, the report argues that the Philippines cannot advance claims that contradict its prior position. For example, it cites a historical Philippine map that places China's Huangyan Dao (Scarborough Shoal) outside Philippine territory.

The report concludes that Manila's subsequent territorial claims violate the post-World War II international order and therefore should not be accepted by the international community.