China's Coast Guard conducted law enforcement patrols in waters east of Taiwan on June 1, responding to Japan and the Philippines' announcement of maritime boundary delimitation negotiations in the area [1, 2, 3, 4]. China regards Taiwan as part of its sovereign territory and views those waters as Chinese territory [1, 2, 3, 4].
China condemned the Japan-Philippines talks as illegal and an infringement on its sovereignty and maritime rights. A China Coast Guard spokesman said, "This is a necessary action taken in response to Japan and the Philippines’ unilateral announcement of the launch of maritime boundary delimitation negotiations in waters east of China’s Taiwan island, which seriously infringes upon China’s territorial sovereignty and maritime rights and interests" [1].
The Japan-Philippines talks were announced at the end of May to delimit their maritime boundary zones under international law, with a focus on areas overlapping their exclusive economic zones extending 200 nautical miles [2, 5, 3, 4]. The two nations are also deepening maritime and defense cooperation amid concerns about China’s expanding presence in the region [6].
Taiwan rejected China’s interference and claims. Its foreign ministry stated, "China has no right to interfere in Taiwan’s territorial sovereignty and sovereign rights over its relevant maritime areas" [2]. Taiwan’s coastguard trailed two Chinese vessels about 51 to 52 nautical miles southeast of Orchid Island on June 1 [5]. Taiwan’s Defense Minister Wellington Koo Li-hsiung said that the navy will support the coastguard as needed [7].
Chinese coastguard activity near Taiwan-controlled Pratas (Dongsha) Islands in the South China Sea has risen sharply, with 39 sightings since February 2025 [7, 4]. On May 29, China’s foreign ministry declared the Japan-Philippines talks illegal and null and void, prompting Taiwan’s foreign ministry to denounce China’s warnings on May 31 [2, 3, 4].
Chinese patrols east of Taiwan continue to respond directly to Japan and the Philippines’ maritime boundary negotiations. Taiwan maintains vigilance and coordination between its coastguard and navy. The maritime talks between Japan and the Philippines are ongoing, with further discussions expected in coming weeks.
