On June 15, 2026, the Chinese-language website of French international broadcaster RFI (Radio France Internationale) reported on the purpose of maritime boundary delimitation negotiations between Japan and the Philippines.

The article stated that Prime Minister Sanae Takaichi and Philippine President Marcos announced a joint statement on a comprehensive strategic partnership and agreed to begin negotiations for the delimitation of maritime boundaries of their exclusive economic zones (EEZ) and continental shelves. It also reported that the Chinese government reacted strongly to this, lodging solemn protests with both Japan and the Philippines.

It further explained that the areas under negotiation extend from near Japan's Yonaguni Island to the Philippines' northernmost Batanes Islands, and that the EEZs of both countries overlap in the waters east of Taiwan, clarifying that these actions are based on the United Nations Convention on the Law of the Sea (UNCLOS). While the Taiwanese authorities emphasized that these actions 'will not affect Taiwan's sovereignty and the enforcement of existing fishing agreements enjoyed under international law and the law of the sea,' China, which views Taiwan as part of its own territory, stated its position that 'it is unacceptable for Japan and the Philippines to delimit boundaries while leaving China out of the picture.'

Furthermore, while stating that the superficial purposes of boundary delimitation are to clarify fisheries management, facilitate the laying of submarine cables, and promote ocean energy development, it pointed out that at a deeper level, there is a geopolitical strategic countermeasure problem of defending the 'first island chain' against the advance of the Chinese military into the 'second island chain.' It also reported that this would help enhance surveillance in the Luzon Strait, Miyako Strait, and the waters around Yonaguni Island, which are important passages for the Chinese navy to enter and exit the Western Pacific, and strengthen security cooperation among Japan, the U.S., and the Philippines, as well as the building of Maritime Domain Awareness (MDA) capabilities.

The article mentioned related Japanese moves, such as the establishment of a working group for the transfer of defense equipment to the Philippines and the provision of patrol vessels, as well as the entry into force of the Japan-Philippines Reciprocal Access Agreement (RAA), parliamentary approval of the Japan-Philippines Acquisition and Cross-Servicing Agreement (ACSA), and the agreement to start negotiations for a General Security Of Military Information Agreement (GSOMIA). It also touched upon holding a summit meeting with Malaysia and signing a memorandum of cooperation between their maritime security agencies.

Furthermore, Japan is attempting to build a vast network to counter China, extending from the East China Sea, Taiwan Strait, and South China Sea to the Strait of Malacca, and aims to deter illegal fishing activities by China's maritime militia, which are regarded as a threat by some countries and regions.

On the other hand, the article reported that China is wary of these movements and has intensified its activities in the waters around Taiwan, with China Coast Guard vessels sailing within Japan's EEZ south of Yonaguni Island and claiming jurisdiction in those waters for the first time. (Edited and translated by Kawashiri)