Foreign Minister Yoko Kamikawa is planning to visit Brunei, Vietnam, Laos and Thailand from Oct. 8 as Japan prepares for a summit with ASEAN leaders later this year, Japanese government sources said Saturday.

In light of China's increasing assertiveness in the South and East China seas, Kamikawa is expected to confirm with her counterparts the importance of ensuring international order based on the rule of law and realizing a free and open Indo-Pacific.

Leaders from Japan and the Association of Southeast Asian Nations are scheduled to meet on Dec. 16-18 in Tokyo to commemorate the 50th year of their friendship and cooperation.

Earlier this month, Japan and the 10-member ASEAN upgraded their relations to a "comprehensive strategic partnership" to further boost cooperation in maritime security and other areas.

The tour will mark Kamikawa's second trip abroad since she assumed the position of foreign minister in a Cabinet reshuffle on Sept. 13. She visited the United States in late September to attend the U.N. General Assembly in New York.

ASEAN groups Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam.

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