By Urvashi Goenka Aug 21 (Reuters) - Most Southeast Asian stock markets were subdued on Monday as worries about U.S. President Donald Trump's ability to fulfil his economic agenda persisted, while Thai shares rose on better-than-expected economic growth data. Thailand's economy expanded at its fastest pace in over four years in the second quarter, led by stronger exports and a boost from the tourism and agricultural sectors, and the government raised its forecasts for economic growth and exports for this year. Financial and energy stocks were among the top gainers with state-owned oil and gas firm PTT Pcl and Central Pattana PCL up over 1 percent each. MSCI's broadest index of Asia-Pacific shares outside Japan was barely in the black, thanks to modest gains in China. Investors were also wary of any flare-up of tensions between North Korea and the United States as U.S. troops and South Korean forces started a joint exercise. Indonesian shares fell 0.5 percent, hurt by consumer and industrial shares. An index of the region's 45 most liquid stocks dropped 0.6 percent. Gudang Garam Tbk PT fell as much as 3.7 percent, while Unilever Indonesia Tbk PT declined up to 1 percent. Malaysian shares fell 0.2 percent as consumer discretionary stocks and financials lost ground. Genting Malaysia declined as much as 1.6 percent, while Hong Leong Bank dropped up to 0.9 percent. The Philippine financial markets were closed for a public holiday. For Asian Companies click; SOUTHEAST ASIAN STOCK MARKETS: Change as of 0443 GMT Change on day Market Current previous Pct Move close Singapore 3253.42 3251.99 0.04 Bangkok 1569.31 1566.53 0.18 Jakarta 5864.409 5893.841 -0.50 Kuala Lumpur 1773.02 1776.22 -0.18 Ho Chi Minh 769.49 768.97 0.07 Change on year Market Current End 2016 Pct Move Singapore 3253.42 2880.76 12.94 Bangkok 1569.31 1542.94 1.71 Jakarta 5864.409 5296.711 10.72 Kuala Lumpur 1773.02 1641.73 8.00 Ho Chi Minh 769.49 664.87 15.7 (Reporting by Urvashi Goenka; Editing by Subhranshu Sahu)