Managing Tensions at Sea: ASEAN Chairmanship and the Philippines’ Strategic Moment

Ongoing disputes in the South China Sea (SCS) are anticipated to be high on ASEAN’s agenda in 2026 as the Philippines assumes leadership of the organization. With July 2026 set as the deadline for ASEAN and China to conclude the Code of Conduct (COC)—a long-awaited framework aimed at regulating behaviors and reducing incidents in the SCS—the Philippines’ chairmanship also comes at a critical juncture. To steer the organization through internal divisions and make substantive headways in negotiations with China, the Philippines should look back to the success of previous chairs.

The ASEAN chair possesses considerable international clout as the bloc’s perceived spokesperson in the broader international community. This reputation is well deserved; through hosting ASEAN summits and high-level meetings, it delivers the agenda and shapes regional priorities. With the group asserting its relevance in the regional security framework amid great power competition, the country holding the chairmanship faces significant pressure to resolve issues within ASEAN and manage its relations with external partners. 

Upon taking the gavel from Malaysia, the Filipino government is hoping to expedite negotiations, facilitating a consensus between ASEAN members and China in the COC.  Meeting these lofty targets requires overcoming increasing constraints both on the ground and at the negotiating table with China. 

Firstly, the Philippines stands unique among its peers in the degree of strife in its relationship with Beijing. Though ASEAN member states share common concerns over China’s aggressive actions in the SCS, their responses have differed markedly. Non-claimant states that do not have immediate interests in the SCS either engage sparingly or excuse themselves entirely, framing the dispute as an internal or bilateral matter. Even direct participants’ strategies diverge according to their risk tolerance level vis-à-vis Chinese pressure. China’s charm offensive diplomacy, marked by a series of high-level visits, is widely seen as further drawing Southeast Asian states away from the Philippines’ hardline posture. It is therefore challenging for the Philippines to mobilize a unified stance among ASEAN members and force China into acquiescence.

Meanwhile, Manila lacks a practical initiative to break deadlocks in the COC negotiation process. Besides disagreement over geographical scope and critical terms used in the code, China and ASEAN hold contrasting views on its legal-binding characteristics and enforcement mechanisms. Whereas China maintains that the COC should be a flexible political document, not subject to a common enforcement mechanism, ASEAN claimants, particularly Vietnam and the Philippines, seek a binding constraint against China’s aggressive behaviour. China’s proposal to ban joint military drills with non-Southeast Asian countries and limit oil and gas exploration during negotiations only further complicated matters. Such restrictions would narrow ASEAN’s strategic room for manoeuvre, running counter to the security strategies of claimant states, including the Philippines, that view external partnerships as essential to deterrence. On account of the imbalance in power between the two parties, the Philippines and ASEAN as a whole are unlikely to be able to impose their demands.

Lessons from past successful chairmanship could offer the Philippines solutions to these problems, specifically the chairmanship of Singapore in 2018 and Indonesia in 2023. Despite its self-identification as a small power with limited leverage, Singapore smoothly brought the SCS claimants back to the negotiating table, drafted the first text of the COC and set the timeframe for future rounds. Indonesia then led ASEAN into the second round of COC negotiation and established the first practical guidelines with China, with a conclusion in mind for 2026. Taken together, these cases show that the ASEAN chair should possess certain leverage, reputation and a mediatory approach with the member states and Beijing to be an effective facilitator.

The Philippines has none of the keys to success of its predecessors. It must look inwards to reform its SCS strategy before assuming regional leadership. First, Manila should recalibrate its ambitions away from finalising the COC in 2026, instead focusing on building an intra-ASEAN stance and finding common ground with China. It could build on the lowest common denominator in current ASEAN members’ strategy—the emphasis on ASEAN centrality—to encourage broader participation, including from non-claimant states, in a multilateral approach. Towards Beijing, Manila should signal a willingness to engage constructively, beginning with reciprocal concessions and a de-escalation of its “assertive initiative.”

As the chair, the Philippines also has both the responsibility and privilege to strengthen and utilize ASEAN’s existing cooperation mechanisms on maritime security to build the group’s leverage against China. One recently emerging initiative is the ASEAN Coast Guard forum, established in 2022 and aimed at promoting maritime cooperation between the members, particularly in non-traditional security. The Philippines can accelerate this mechanism’s institutionalization under the ASEAN framework and expand its scope to include the forces of external powers. 

The Philippines altogether has a critical opportunity to shape rules-based governance in SCS disputes. The COC negotiations will serve as an important litmus test for Manila’s leadership and ASEAN’s ability to both manage internal divisions and assert itself as a regional norm-shaping institution. Failure to deliver meaningful progress on the COC and broader maritime security initiatives would further cast doubt on ASEAN’s credibility and relevance at a time when the regional and global order is increasingly volatile and rules are being eroded.

References

1. Chi, C. (2025) ‘Philippines ready to propose more frequent Code of Conduct talks as ASEAN chair,’ Philstar.com, 17 November. https://www.philstar.com/headlines/2025/11/17/2487926/philippines-ready-propose-more-frequent-code-conduct-talks-asean-chair. 
2. Heng, Y.K. (2015) ‘ASEAN’s Position on the South China Sea and Implications for Regional Peace and Security,’ in Palgrave Macmillan UK eBooks, pp. 69–81. https://doi.org/10.1057/9781137463685_5. 
3. Ian, C.J. (2023) ‘Herding Cats,’ China Review, 23(1), pp. 307–339. https://www.jstor.org/stable/48717997. 
4. Jiangtao, S. (2024) ‘Beijing uses ‘divide and conquer’ tactic with Asean as South China Sea tensions heat up,’ South China Morning Post, 26 September. https://www.scmp.com/news/china/diplomacy/article/3277495/beijing-uses-divide-and-conquer-tactic-asean-south-china-sea-tensions-heat. 
5. Lin and Sothirak, P. (2025) ‘The Elusive Code: Why ASEAN Needs a New Playbook for the South China Sea,’ ISEAS – Yusof Ishak Institute, 26 June. https://www.iseas.edu.sg/articles-commentaries/iseas-perspective/2025-39-the-elusive-code-why-asean-needs-a-new-playbook-for-the-south-china-sea-by-joanne-lin-and-pou-sothirak/. 
6. Mon, S.W., Nguyen, T. and Gabriel Mendoza, J. (2025) ‘Securing Southeast Asian waters: Formalising the role of the ASEAN Coast Guard Forum,’ Lowy Institute, 4 February. https://www.lowyinstitute.org/the-interpreter/securing-southeast-asian-waters-formalising-role-asean-coast-guard-forum. 
7. Ng, J. (2018) ‘Singapore’s ASEAN Chairmanship: Advancing Peace & Security,’ RSIS, 16 November. https://rsis.edu.sg/rsis-publication/rsis/singapores-asean-chairmanship-advancing-peace-security/. 
8. Prajapati, H. (2026) ‘Facing China, Southeast Asia needs to boost coast-guard cooperation,’ The Strategist, 15 January. https://www.aspistrategist.org.au/facing-china-asean-coast-guard-forums-institutionalisation-would-bolster-regional-capability/ .
9. Reuters (2025) Philippines Eyes Completion of South China Sea Code as ASEAN Chair Next Year. https://www.usnews.com/news/world/articles/2025-11-17/philippines-eyes-completion-of-south-china-sea-code-as-asean-chair-next-year. 
10. Strangio, S. (2025) ‘Philippines Hoping to Conclude South China Sea Code of Conduct in 2026,’ The Diplomat, 18 November. https://thediplomat.com/2025/11/philippines-hoping-to-conclude-south-china-sea-code-of-conduct-in-2026/. 
11. The Indonesian Ministry of Foreign Affairs and Reuters (2024) Indonesia Takes Leadership in South China Sea Code of Conduct Negotiations – Politics Today. https://politicstoday.org/indonesia-south-china-sea-code-of-conduct/. 
12. Venkataramani, B. (2025) ‘With the Philippines as ASEAN chair, a South China Sea agreement is unlikely to be concluded in 2026,’ Chatham House, 9 December. https://www.chathamhouse.org/2025/12/philippines-asean-chair-south-china-sea-agreement-unlikely-be-concluded-2026.
13. Wang, X. and Wang, S. (2026) ‘Risk tolerance and domestic nationalism response demand: explaining South China Sea claimants’ responses to China (2010–2025)’, The Pacific Review, pp. 1–34. doi: 10.1080/09512748.2026.2615114.

Zheng, W. (2026) ‘A Media Analysis of Beijing’s Head-of-State Diplomacy in Southeast Asia,’ ISEAS – Yusof Ishak Institute, 15 January. https://www.iseas.edu.sg/wp-content/uploads/2025/10/ISEAS-Perspective_2026_3.pdf