As the Philippines prepares to lead the Association of Southeast Asian Nations (ASEAN) in 2026, Manila’s leaders have vowed to press for a legally binding code of conduct (COC) between the 11 member nations and China. The agreement would codify rules for behavior in the economically important sea and reduce the risk of maritime clashes.
Beijing’s posture, however, remains a fundamental obstacle. Despite years of talks, China has resisted an agreement that would meaningfully constrain its aggression or recognize international laws and norms.
China claims most of the South China Sea, including territory in the Bruneian, Indonesian, Malaysian, Philippine and Vietnamese exclusive economic zones (EEZ). Beijing also defies the 2016 ruling of an international arbitral tribunal, convened under the United Nations Convention on the Law of the Sea, which invalidated China’s vast claims.
China’s coast guard, navy and maritime militia have intensified a campaign of aggression against the Philippines in particular, ramming, blocking and using water cannons to harass military patrols, fishing vessels and humanitarian missions operating lawfully in Manila’s EEZ.
ASEAN and China agreed in 2002 to create a COC, although talks did not begin for 15 years. Multiple rounds of discussion and draft texts have not produced a final pact.
Legal and strategic disagreements have stalled the process, analysts say. “China’s preference for a non-binding flexible COC that avoids external scrutiny and ASEAN-led monitoring mechanisms stands in stark contrast to the positions of some ASEAN countries that seek a robust, legally grounded agreement,” wrote researchers with the Singapore-based Yusof Ishak Institute (ISEAS). “This fundamental divide continues to obstruct convergence on key provisions such as scope, definitions and enforcement.”
Observers say China is likely to continue using economic and trade coercion in an attempt to strong-arm ASEAN nations and insist on flexible language instead of legally binding commitments.
During negotiations, Beijing also has proposed banning military drills with countries outside Southeast Asia.
The Philippines has bolstered its defense cooperation with Allies and Partners including Australia, Japan and the United States in response to China’s threats and aggression. Manila “is likely to view its external defense partnerships as the most realistic means of safeguarding its sovereignty in the South China Sea,” The Diplomat magazine reported.
Meanwhile, China’s arbitrary claims to the sea remain nonnegotiable under Chinese Communist Party General Secretary Xi Jinping, analysts said in the ISEAS journal Fulcrum. “This makes China resistant to any COC text that would dilute its control or open the door to international scrutiny. While it may support a legally binding COC, it will likely do so only if its preferred language is accepted.”
The COC could instead be a “living instrument” focusing on a realistic, regionally credible and enforceable agreement “that is refined incrementally until it is capable of meaningfully shaping behavior and preserving stability in the South China Sea,” ISEAS senior fellow Joanne Lin and former Cambodian ambassador Pou Sothirak wrote for Fulcrum.
They recommend confidence-building measures between ASEAN nations and China, including naval and coast guard hotlines and advance notice of military exercises.
Experts also emphasize the Philippines’ leverage in protecting its territorial sovereignty. The nation’s transparency strategy — exposing China’s aggression to the international community — combines with the decade-old arbitral ruling to give Manila moral authority in the dispute, in addition to regional and international backing.