Taiwan's Ministry of Foreign Affairs (MoFA) on Sunday, 2 August reaffirmed its sovereignty claim over islands in the South China Sea, responding directly to the Philippines' decision to deposit an official nautical chart of Scarborough Shoal with the United Nations. Taipei also called for its inclusion in multilateral dispute-settlement mechanisms, according to reports from Taiwan's Central News Agency (CNA).

What Triggered Taiwan's Statement

The Philippines' Department of Foreign Affairs submitted the nautical chart to the UN last week, citing Article 16 of the 1982 United Nations Convention on the Law of the Sea (UNCLOS), which requires coastal states to publicise official charts depicting the baselines from which the breadth of the territorial sea is measured. Manila's move was aimed at reinforcing its own claim over the atoll.

Scarborough Shoal — known as Bajo de Masinloc in the Philippines, Democracy Reef in Taiwan, and Huangyan Dao in China — is simultaneously claimed by all three nations, making it one of the most contested maritime features in the region.

Taiwan's Position

Taiwan's MoFA stated that any disputes in the South China Sea must be resolved peacefully and in accordance with international law and the law of the sea. Crucially, Taipei demanded that it be included in multilateral dispute-settlement forums — a long-standing ask that reflects Taiwan's exclusion from most international bodies due to its disputed political status.

China's Sharp Rejection of Manila's Move

On 31 July, China's Ministry of Foreign Affairs condemned the Philippines' chart submission, calling it 'illegal, null, and void' and describing it as 'a grave infringement' upon China's territorial sovereignty and 'a serious violation of international law, including the United Nations Charter and UNCLOS.'

Beijing stated: 'China firmly rejects and will never accept it. Huangyan Dao is China's inherent territory. China has indisputable sovereignty over it and its adjacent waters, and has sovereign rights and jurisdiction over the relevant waters.'

China further argued that the Philippines' 'unilateral initiation of the South China Sea arbitration' violates fundamental principles of international law, including the bilateral agreement between the two countries and the Declaration on the Conduct of Parties in the South China Sea (DOC). Beijing maintained that the territory of the Philippines has been defined by a series of international treaties and that Huangyan Dao 'has never been a part of it.'

Why This Escalation Matters

The Philippines' UN filing and the swift responses from both Taipei and Beijing signal a new phase of legal and diplomatic manoeuvring over the South China Sea. This is not the first time the three claimants have clashed over Scarborough Shoal — the atoll has been a flashpoint since China effectively took control of it in 2012, following a standoff with Philippine vessels. The Philippines secured a landmark ruling from the Permanent Court of Arbitration in 2016, which invalidated China's broad maritime claims, though Beijing has consistently rejected that verdict.

Taiwan's call for inclusion in settlement mechanisms adds a further layer of complexity, as Taipei is excluded from the UN system and most international legal forums. With all three claimants now publicly staking positions in quick succession, the risk of diplomatic friction in the South China Sea appears to be rising heading into the second half of 2025.