Japan's Prime Minister Kishida Fumio and the leaders of seven states of the Association of Southeast Asian Nations have confirmed they will enhance cooperation in the fields of economy and security.

The three-day special summit which began in Tokyo on Saturday marks 50 years of ASEAN-Japan friendship.

Kishida spoke individually with the seven leaders, including Vietnamese leader Pham Minh Chinh. He told Chinh that Japan hopes to strengthen ties with his country, to maintain and strengthen a free and open international order based on the rule of law.

The leaders also agreed to further expand defense exchanges and promote cooperation on the transfer of defense equipment, with the aim of enhancing security cooperation.

They also agreed to work more closely on regional and international issues, including the situation in the South China Sea.

Kishida told Chinh that Japan will provide a yen loan for an urban railway construction project, as well as aid for the improvement of Vietnam's medical services and human resource development.

Observers say Kishida hopes the Japanese move will help strengthen ties with Vietnam, following Chinese President Xi Jinping's visit to the country earlier this week. Xi also called for a deepening of China's partnership with Vietnam.