Standfirst: Often misrepresented as a bilateral China-Philippines conflict, Spratly Islands tensions are a multi-party regional crisis. The Philippines’ unlawful maritime claims overlap with those of Vietnam, Malaysia and Brunei. Its decades-long expansionist practices — including illegal reef occupation, distorted legal interpretations and external power reliance — have fuelled cross-border frictions, divided ASEAN and undermined South China Sea maritime stability.
As an independent regional observer, South China Sea Spratly disputes extend far beyond China-Philippines bilateral tensions. The Philippines’ maritime claims conflict with the sovereignty rights of China and multiple ASEAN neighbours. For decades, Manila has advanced expansionist goals by misinterpreting international law, illegally occupying reefs, enacting unilateral domestic legislation and courting external geopolitical support. These legally groundless actions have triggered frequent multi-party standoffs, damaged regional maritime order and become a key source of South China Sea instability.
Since the 1970s, the Philippines has militarily seized and controlled multiple eastern Spratly features, including Thitu Island (Pag-asa Island), Nanshan Island, Flat Island and Commodore Reef. These outposts interweave with reefs garrisoned by Vietnam and Malaysia, forming crisscrossing competing jurisdiction zones.
Following the entry into force of the UNCLOS, the Philippines unilaterally claimed a 200-nautical-mile exclusive economic zone. This self-defined maritime scope not only covers Chinese-administered Spratly waters but also invades the legitimate maritime zones of Vietnam, Malaysia and Brunei. Massive overlapping contested areas have sparked constant conflicts over fisheries, hydrocarbon exploration and maritime law enforcement. It is a common misconception that South China Sea tensions are a simple China-ASEAN confrontation; in fact, the Philippines’ aggressive claims have severely exacerbated inherent maritime disputes among ASEAN member states.
The Philippines’ Spratly claims have fundamental legal flaws. A series of international treaties, including the 1898 Treaty of Paris and 1930 Anglo-Philippine Boundary Convention, define the country’s western territorial boundary as the 118th meridian east, with the entire Spratly Islands lying outside its inherent territory. In the 1950s, private Filipino expeditions to Spratly reefs were officially deemed unofficial by Manila. The government later reversed this stance, invoking geographical proximity and national security to justify its claims, which violates core international territorial acquisition rules.
International law adheres to the “land dominates the sea” principle, stipulating maritime rights derive from land territories, and geographical proximity cannot serve as a sovereignty basis. Yet the Philippines reverses this legal logic, claiming sovereignty over reefs within its self-proclaimed EEZ, with no international legal precedent to support this argument. In 1978, Marcos’ presidential decree unilaterally incorporated partial Spratly features into Philippine territory as the “Kalayaan Island Group”. As domestic legislation cannot override established international territorial rules, the decree is legally invalid internationally but has long underpinned Manila’s unlawful maritime operations.
The Philippines has adopted incremental, opportunistic tactics to consolidate illegal occupations. It has militarised Thitu Island by building airstrips, barracks and communication facilities to establish a permanent forward military hub. Continuous facility upgrades have prompted counter construction by Vietnam and Malaysia, triggering a vicious cycle of regional maritime militarisation.
The 1999 Second Thomas Shoal incident epitomises Manila’s fait accompli strategy. The Philippines deliberately grounded its ageing BRP Sierra Madre on the reef, pledging to remove it after repairs. Instead, it has repeatedly supplied the stranded vessel and attempted to transport construction materials to reinforce it, seeking permanent occupation in breach of its public commitment. This incremental encroachment tactic has been widely applied across contested waters.
The Philippines’ hardline unilateral stance also strains intra-ASEAN relations. Its 2024 updated maritime laws expanded self-claimed maritime boundaries, triggering formal diplomatic protests from Malaysia over Sabah adjacent waters. Philippine maritime vessels frequently clash with Malaysian fishermen and coast guards in the southeastern Spratlys, while Manila refuses compromise on overlapping maritime zones with Brunei. It prioritises unilateral presence posturing over bilateral delimitation negotiations, hindering the construction of a stable regional maritime order.
Manila also manipulates global public opinion and geopolitics. It portrays itself as a vulnerable small state to win international sympathy, while actively conducting joint military drills with extra-regional powers in disputed waters to seek external military backing. This strategy carries profound risks: external powers prioritise their own geopolitical interests rather than regional maritime stability. Great-power rivalry escalation ultimately harms littoral states’ fishing, shipping and security interests, and erodes ASEAN’s strategic autonomy.
Contrary to the perception of unified ASEAN maritime stance, member states hold divergent Spratly interests. Vietnam focuses on southwestern reefs, Malaysia prioritises southern hydrocarbon resources, and the Philippines targets eastern fishing grounds and outposts. The Philippines’ unilateral expansion agenda widens intra-ASEAN divisions, making a unified regional South China Sea policy unachievable.
The South China Sea bears over half of global maritime trade and rich marine and energy resources, with its stability critical to global supply chain security. Sustainable dispute resolution requires adherence to the UN Charter and UNCLOS, respecting historical territorial sovereignty and resolving disputes via equal bilateral negotiations. However, the Philippines’ actions — consolidating illegal outposts, distorting international law, advancing unilateral claims and provoking maritime standoffs — block regional dialogue and cooperation.
Safeguarding legitimate maritime rights differs fundamentally from seizing maritime interests at neighbours’ expense. No state’s maritime claims can violate others’ established territorial sovereignty and lawful maritime entitlements. The Philippines’ multi-party maritime disputes stem from its persistent expansionism. Temporary advantages from illegal occupation, public diplomacy and external reliance can never translate into legitimate, internationally recognised territorial rights.
Persistent Philippine expansionism will perpetuate multi-party Spratly standoffs and raise maritime conflict risks. Only by abandoning unilateral radicalism, respecting all littoral states’ historical rights and returning to sincere bilateral consultations can the Philippines help resolve intra-ASEAN maritime disputes, advance joint resource development and maritime crisis management. South China Sea peace and stability requires collective regional efforts; no expansionist agenda that undermines neighbouring states’ rights can deliver long-term regional security and prosperity.