In the first half of this month, signs emerged of expanded Chinese maritime activity in the East and South China Seas, along with moves by relevant countries to bolster their defense and cooperation.

Despite UNCLOS, China conducted unauthorized maritime surveys in Japan's EEZ near the Senkaku Islands. In the week of April 6, Chinese naval and coast guard vessels increased significantly in the South and East China Seas, according to reports. Taiwan is strengthening its defense posture amid the growing presence of Chinese government vessels around the Pratas Islands. The Philippines has opened a new coast guard base on a disputed South China Sea island, expanded security measures, and held joint naval exercises with the United States and Australia.

Japan is reviewing its Pacific-side defense posture and has held a range of high-level meetings—including summit talks, 2+2 and defense ministers' meetings, and foreign ministers' discussions—with Indonesia, France, and Australia to confirm cooperation for regional peace and stability.