Ministerial-level defense representatives from Japan and 13 Pacific island countries vowed on Thursday in an online meeting to tighten cooperation to maintain maritime order amid China's increasing military activity in the region.

The participants in the first such gathering affirmed the importance of promoting a free and open Indo-Pacific, their joint statement said. The concept is an initiative by the United States and Japan, apparently aimed at countering Beijing's rising assertiveness in the nearby waters and its growing economic influence in the region.

The representatives agreed on the need for their "mutual understanding and trust-building to address challenges for regional security," the statement said.