The Permanent Court of Arbitration’s (PCA) ruling in the South China Sea case filed by the Philippines has been labelled a ‘sweeping victory’ against China. It concluded that China has no legal basis to claim historic rights within the nine-dash line in the South China Sea and that none of the land features in the Spratlys meet the criteria for an island that China — or any other country — can use to claim a 200-nautical-mile exclusive economic zone (EEZ).

Many countries — including the United States, Australia and Japan — welcomed the arbitration outcome and pressured China to comply with the ruling. Unsurprisingly, China rejected the tribunal’s ruling, and reasserted its ‘indisputable sovereignty’ over the South China Sea. The Chinese Foreign Ministry stated that the tribunal’s ruling is invalid and China does not ‘accept or recognise it.’ Although the original purpose of the arbitration was to resolve maritime disputes in the South China Sea, this ruling will have unintended negative consequences for regional security.

The Tribunal’s ruling breaks the ‘balance of ambiguity’ in the South China Sea disputes. One major cause of competing claims is the inherently ambiguous terms of the 1982 UN Conventions of the Law of the Sea (UNCLOS). Different claimants have interpreted the law to make claims in their own favour. No country has unchallenged claims in the South China Sea.

Although the legal ambiguity may make it hard to resolve the disputes, it provides a certain flexibility for all claimants to manage their behaviour and leaves room for compromises if necessary.

Please click here to read the full “South China Sea ruling won’t improve regional security” article in East Asia Forum by Griffith Asia Institute Associate Professor Kai He and School of Government and International Relations Senior Lecturer Dr Huiyun Feng.