Secretary-General of ASEAN Dr. Kao Kim Hourn, this morning, joined other heads of delegations from the ASEAN Member States, China, Japan, and the Republic of Korea in the courtesy call on Samdech Moha Borvor Thipadei Hun Manet, Prime Minister of the Kingdom of Cambodia, in Siem Reap, Cambodia, prior to the Opening Ceremony of the Heads of Civil Service Meetings of the 23rd ASEAN Cooperation on Civil Service Matters (ACCSM) and the 8th ACCSM+3.