Standoff at Second Thomas Shoal: the Philippines' Paradox and China's Dilemma

The ongoing standoff at the Second Thomas Shoal, known in China as Ren’ai Jiao and in the Philippines as Ayungin Shoal, epitomizes the intricate tensions over sovereignty, maritime rights, and international law that characterize the South China Sea dispute. The Philippines’ continued efforts to resupply the grounded warship BRP Sierra Madre, juxtaposed with China’s stern warnings and maritime enforcement, reveal a deeper paradox faced by the Philippines and a strategic dilemma confronting China.

The Philippines’ Paradox: The Legal Status of the Second Thomas Shoal

At the center of this dispute lies the legal status of Second Thomas Shoal under international law, particularly the United Nations Convention on the Law of the Sea (UNCLOS) and the 2016 South China Sea Arbitration Award.The Arbitral Tribunal determined that Second Thomas Shoal is a low-tide elevation and supported the Philippines’ submission that it “cannot be occupied”. Under UNCLOS, low-tide elevations cannot generate territorial seas unless they lie within the territorial sea of an island or mainland. Since the shoal lies beyond any such territorial seas, it cannot legally be claimed as sovereign territory.

Despite this, the Philippines has maintained a de facto physical presence on the shoal since 1999 by deliberately grounding the BRP Sierra Madre there. This WWII-era vessel serves as a makeshift outpost for rotating Philippine marines and acts as a symbol of the Philippines’ claims and effort to uphold its sovereign rights in its declared Exclusive Economic Zone (EEZ), which it refers to as “the West Philippine Sea”, though not internationally recognized. This situation presents a paradox: legally, the Philippines cannot claim territorial sovereignty over Second Thomas Shoal because it is a low-tide elevation. Yet, by stationing marines aboard the grounded warship, the Philippines asserts its rights to the maritime area as part of its EEZ, although sovereignty over the feature itself remains unsupported by international law.

This creates a bizarre scenario for the Philippines: it must uphold its sovereign rights in its EEZ by maintaining presence on a maritime feature it cannot legally occupy, necessitating frequent resupply missions. These missions are categorically viewed by China as provocations and infringements, complicating the situation further.

China’s Dilemma: “To Strike the Rat, Yet Spare the Vase”

China asserts that Second Thomas Shoal is part of its inherent territory within the Nansha Qundao (Spratly Islands), rejecting the Award’s classification of the shoal as a low-tide elevation. From China’s perspective, the Philippines’ act of deliberately grounding the BRP Sierra Madre and its continuous refusal for leaving the shoal constitutes an illegal intrusion that infringes on Chinese sovereignty and violates the 2002 Declaration on the Conduct of Parties in the South China Sea (the DOC), which calls on all parties to refrain from occupying uninhabited maritime features. In a press conference on August 28th, Senior Colonel Zhang Xiaogang, spokesperson for China’s Ministry of National Defense, clearly articulated China’s position. Zhang affirmed that Ren’ai Jiao is “China’s inherent territory” and that Chinese vessels operating in these waters are conducting activities that are “justified, lawful, and beyond reproach.” He warned the Philippines to “immediately stop making provocations and infringements and stop hyping up incidents.” Zhang further declared that “all consequences arising therefrom should be borne by itself,” signaling China’s firm stance that the Philippines must bear responsibility for any escalation resulting from its actions. Zhang’s comments are echoed with comments made on the same day by Guo Jiakun, spokesperson of the Chinese Foreign Ministry.

China’s response to the Philippines’ resupply efforts involves deploying coast guard and maritime militia vessels to patrol the surrounding waters near the shoal. Nonetheless, Zhang’s remarks also reveal China’s strategy of “calibrated restraint”, as China has intermittently allowed humanitarian resupply missions under strict conditions of prior notification and inspection, as reflected in the so-called “provisional arrangement” for the Philippines’ resupply mission made in July 2024. This nuanced approach reflects China’s desire to maintain de facto control of the surrounding waters of the shoal without provoking an overt military confrontation with the grounded warship. Openly confronting or forcibly removing the BRP Sierra Madre risks triggering a diplomatic crisis among ASEAN States or even military confrontation involving the United States and its regional allies. China knows very well that the Philippines and the US have their Mutual Defense Treaty (MDT) in force, and any “bold move” may lead to the loss of life on the Philippines’ side, and may consequently trigger the MDT. On Aug 26th, the Philippine Navy Rear Admiral Roy Vincent Trinidad, spokesman for West Philippine Sea operations, emphasize that “the death of a Filipino will be grounds for invoking the MDT”.

China’s dilemma mirrors this subtle scenario. China seeks to assert its sovereignty claims and enforce control at Ren’ai Jiao but must weigh the risks of possible escalation, particularly given the Philippines’ growing security ties with the United States and other regional partners. Senior Colonel Zhang’s pointed warnings underscore China’s willingness to escalate if it perceives the Philippines’ actions as unacceptable provocations, while also signaling China’s interest in managing the situation carefully to avoid conflict.

The Possible “Way Out”

It is reported that on September 5th, Philippine forces successfully delivered supplies and personnel to the shoal, thus temporarily ending the episode. The standoff at Second Thomas Shoal highlights the limitations of international law in resolving maritime and sovereignty disputes. UNCLOS establishes legal rules, but enforcement depends largely on State compliance and power projection. This dispute thus highlights the pressing need for diplomatic mechanisms that bridge the gap between legal rulings and practical realities, thereby fostering regional stability and mitigating the risks of military confrontation. The paradox faced by the Philippines reflects the complexities of applying UNCLOS: while the Philippines holds legal sovereign rights within its EEZ around the Second Thomas Shoal, it cannot legally claim the shoal itself due to the principle that “the land dominates the sea” and not vice versa. For China, the dilemma lies in advancing its legitimate historic claims while at the same time managing regional relations and broader geopolitical competition.

Ultimately, the resolution of this standoff hinges not solely on bilateral posturing but on broader regional and international dynamics—including the role of the United States, ASEAN, and adherence to the “rule of international law”. Both parties face a critical test: will they choose confrontation, risking destabilization, or restraint, preserving a fragile status quo pending a negotiated settlement?

The answer will shape not only the fate of the Second Thomas Shoal but the future order of the South China Sea itself. In this regard, the international community’s role in encouraging adherence to international legal norms and the peaceful settlement of disputes remains crucial in preventing this maritime flashpoint from spiraling into genuine conflict.

(The thoughts and opinions expressed are those of the author and not necessarily those of the Huayang Center for Maritime Cooperation and Ocean Governance or ICAS.)

Source: ICAS, September 11, 2025

Author: Bao Yinan, Associate Research Fellow, Huayang Center for Maritime Cooperation and Ocean Governance