evidence: Lao Prime Minister Thongloun Sisoulith and his Cambodian counterpart Samdech Techo Hun Sen will attend the opening ceremony of the new Nong Nokkhiane - Trapeang Kriel international border checkpoint which links the Nong Nokkhiane area in Khong district of Champassak province in southern Laos and the Trapeang Kriel area in Cambodia's northeastern Stung Treng province. The opening of the international checkpoint follows the agreement between the two governments in April 9, 2009, to upgrade the local border with the aim of providing convenience to people crossing in the area. Laos and Cambodia have agreed to promote investment and trade cooperation between their neighboring provinces after the value of bilateral trade reached 24.5 million U.S. dollars in 2015, reported Lao state-run Vientiane Times. According to a press release by Cambodian Ministry of Foreign Affairs and International Cooperation on Wednesday, after the inauguration ceremony, the Cambodian prime minister will visit Don Sahong Hydropower Dam in Laos' Champasak province.