When ASEAN foreign ministers gathered in Cebu in January 2026, they gave themselves a deadline: conclude a substantive Code of Conduct for the South China Sea by the end of this year. Six months later, the gap between that diplomatic ambition and the physical reality on the water has never been wider. The COC remains a document in negotiation. Meanwhile, construction continues on contested features, coast guard confrontations multiply, and the claimants proceed on the assumption that time is on their side.

The 26th ASEAN-China Senior Officials’ Meeting convened in Kuala Lumpur on May 21, the latest in a series of accelerated monthly technical consultations aimed at meeting the 2026 target. Both sides have publicly committed to concluding a legally binding COC — a significant shift from the non-committal language of previous years. But experts who track the South China Sea dispute closely caution that commitment and outcome are different things.

“Little substantive progress has been made since the signing of the Declaration on the Conduct of Parties in the South China Sea in 2002,” maritime analyst Nazery Khalid told Bernama. The DOC was a political document. It carried no enforcement mechanism. Twenty-four years later, ASEAN and China are attempting to build a legally binding framework atop the same structural fault lines that made the DOC aspirational rather than operational.

The central obstacle has not changed: national interests, domestic political pressures, and geopolitical alignment continue to shape each claimant’s willingness to accept meaningful constraints. Cambodia and Laos — both close to Beijing — have consistently blocked language that major ASEAN members including Vietnam, the Philippines, and Malaysia would otherwise support. The consensus rule that governs ASEAN decision-making means that a single member can dilute a final text. The result is invariably language both sides can live with and no party genuinely fears.

Professor Leong Kok Wey of the National Defence University of Malaysia proposed an interim measure: a provisional COC agreement that would take effect while negotiators continue refining outstanding details over subsequent years. “This would demonstrate the seriousness and credibility of ASEAN and China in managing regional issues in their own way without interference from other powers,” he told Bernama. A provisional agreement, even without final enforcement provisions, could function as a confidence-building measure — a “living document” that would evolve as both sides accumulated experience operating within its framework.

On the water, however, neither side is waiting for a document to be finalized. On May 19, a resupply mission to Second Thomas Shoal — contested waters 200 kilometers from Palawan — encountered what the Philippine Coast Guard described as “illegal, aggressive and destabilizing” actions by China Coast Guard and maritime militia vessels. The mission succeeded. Supplies reached the troops aboard the BRP Sierra Madre, the World War II-era ship Manila intentionally grounded on the shoal in 1999 to reinforce its territorial claim. But the confrontation was the latest in a pattern that has grown steadily more dangerous over the past two years.

China rejected Manila’s account. Beijing insists its coast guard acted lawfully in waters it considers under Chinese jurisdiction. China also accused the Philippines of transporting construction materials to reinforce what it calls an “illegally grounded warship.” The exchange of accusations reflects a deeper problem: both sides operate from legal positions that the other considers inherently illegitimate. The 2016 arbitral ruling, delivered by an international tribunal under UNCLOS, found that China’s nine-dash line claims had no basis in international law. Beijing refuses to acknowledge the ruling. Manila bases its own assertions on it daily. No COC text can paper over a conflict between legally incompatible positions unless it resolves the underlying question — which no COC, as currently conceived, is designed to do.

The Philippine government, serving as ASEAN Chair for 2026, has proposed establishing an ASEAN Maritime Centre — a body that would support ASEAN-led mechanisms on maritime-related issues and promote cross-sectoral cooperation across member states. President Ferdinand Marcos Jr. has been careful to frame the proposal as not directed against any country. That framing is diplomatically necessary. It is also analytically accurate in the narrowest sense: the centre would serve cooperation across maritime security, blue economy development, and environmental protection. It does not challenge anyone’s claims. It does not alter the military balance. It creates one more forum for talking about a problem that existing forums have not resolved.

The Trump-Xi summit, now concluded, added a further complication. Whatever bilateral understanding emerged from that meeting — and the details remain contested — altered the calculus for every ASEAN member with a South China Sea interest. The regional architecture in the South China Sea has never been solely a matter of the ten ASEAN states and China. The United States has been a silent guarantor of the balance of power since the 1970s. Its current administration’s approach to alliance management, trade, and the broader Indo-Pacific has introduced uncertainty into calculations that were already difficult.

The honest assessment is this: a COC concluded on schedule by December 2026 would be significant. It would represent the first legally binding framework governing conduct in disputed waters. It would not resolve the fundamental conflict between Beijing’s nine-dash line and the UNCLOS-based claims of its neighbors. It would not stop construction. It would not prevent confrontations like the one at Second Thomas Shoal last week. What it might do — if it includes effective confidence-building mechanisms, real notification requirements, and dispute resolution procedures that parties actually use — is lower the temperature enough that the next round of negotiations can address the harder questions. That is worth pursuing. It is not a substitute for the harder work of building actual deterrence.