Indonesia's Incumbent President Joko Widodo attends a plenary session during the 34th ASEAN Summit in Bangkok, Thailand, June 22, 2019. Southeast Asian leaders agreed on Sunday to work together on the region's economy and security to strengthen their position to face growing U.S.-China tensions, as they wrapped up their summit in Bangkok. ANTARA/Puspa Perwitasari

Thai Prime Minister Prayut Chan-o-cha (right) leads the 34th ASEAN Plenary Session in Bangkok, Thailand, Saturday, June 22, 2019. The 10-member Association of Southeast Asian Nations (ASEAN) will need its collective economic strength for bargaining power globally, especially amid the trade tensions between the world's top two economies, Thai Prime Minister Prayuth Chan-ocha told a news conference, as chairman of the 34th ASEAN Summit. ANTARA/Puspa Perwitasari

Brunei's Sultan Hassanal Bolkiah, Cambodia's Prime Minister Hun Sen and Indonesia's Incumbent President Joko Widodo attend a plenary session during the 34th ASEAN Summit in Bangkok, Thailand, June 22, 2019. Prayuth urged ASEAN nations to complete negotiations this year for the China-initiated Regional Comprehensive Economic Partnership (RCEP) pact that includes 16 countries but has been held up by disputes between China and India over access to markets and protected lists of goods. ANTARA/Puspa Perwitasari

Indonesia's Incumbent President Joko Widodo attends a plenary session during the 34th ASEAN Summit in Bangkok, Thailand, June 22, 2019. Negotiations began in 2012 on RCEP, which envisages the creation of a free trade zone encompassing 45% of the world's population and more than a third of its GDP, but does not involve the United States. REUTERS/Jorge Silva

Indonesia's Incumbent President Joko Widodo attends for a plenary session during the 34th ASEAN Summit in Bangkok, Thailand, June 22, 2019. First proposed by China, RCEP's 16 signatories comprise the 10 ASEAN member states and six Asia-Pacific countries, including major economies China, India, Japan and South Korea. ASEAN has existing free-trade agreements with all six countries. ANTARA/Puspa Perwitasari

The atmosphere of the 34th ASEAN Plenary Session in Bangkok, Thailand, Saturday, June 22, 2019. "If we can do this, we will have the bargaining power and base for negotiation. Because when combined, we are 650 million people, the largest regional bloc in the world," the Thai prime minister said of ASEAN. ANTARA/Puspa Perwitasari