The Pacific Islands Leaders Meeting has kicked off a three-day summit in Tokyo on Tuesday.

Japan hosts the summit of leaders from South Pacific island nations and other countries once every three years. The 10th gathering this year brings together Japan and 18 countries and territories from the region.

Japan's Prime Minister Kishida Fumio held meetings with the leaders from Tuvalu and Vanuatu on the first day.

Kishida told Tuvalu's Prime Minister Feleti Teo that he wants to take this opportunity to show the world that Japan will strengthen ties and work together with the Pacific island nations.

In the meetings, Kishida is likely to have confirmed cooperation over various issues including climate change and maritime security. He is also believed to have called for understanding of Japan's discharge of treated and diluted water from the crippled Fukushima Daiichi nuclear power plant.

Before releasing the treated water into the ocean, the plant's operator dilutes it to reduce the tritium levels to about one-seventh of the World Health Organization's guidance level for drinking water.

All the representatives will join a meeting for final discussions on Thursday. They plan to issue a joint statement detailing the outcome of the meetings.

Japan hopes to use the summit to strengthen ties with the South Pacific island countries, amid China's efforts to increase its presence in the region through infrastructure projects.