* Malaysian stocks hit highest since Aug. 9 * Indonesia sees worst session in 11 days * Thai index slightly up ahead of Nov. trade data By Shruti Sonal Dec 30 (Reuters) - Most Southeast Asian markets rose on Monday, with Malaysian equities hitting an over 4-month high, as investor sentiment was buoyed by positive developments around the Sino-U.S. trade deal. South China Morning Post quoted a Chinese official saying that ­Beijing will live up to its trade deal commitments, but the United States must also honour the one-China policy in relation to Taiwan. The remarks come as ­Beijing and Washington announced a Phase 1 trade deal earlier this month, cooling their 18-month trade war that has rattled financial markets and hurt global economic sentiments. Aiding sentiment was a Xinhua News Agency report that retail sales in China, the biggest trading partner of most Southeast Asian countries, are expected to increase 8% in 2019. Malaysian shares hit their highest since Aug. 9 as consumer and utilities jumped. Genting Malaysia Bhd and Petronas Gas Bhd were the top gainers. Singapore stocks eked out gains on strength in utilities and industrials. Index heavyweight Singapore Telecommunications Ltd climbed as much as 0.9% on news that it is partnering with ride-hailing firm Grab Holdings Inc to apply for a digital full banking licence in Singapore. Thai benchmark index was up slightly ahead of official November trade data announcement, even as volumes remained low on its last trading day of the year. Earlier this month, commerce ministry data showed that the country recorded a trade surplus of $0.55 billion in November, compared with a Reuters forecast of a $0.19 billion deficit. Indonesian stocks fell 0.2%, marking their worst session in 11 days, dragged down by technology and utilities. IT firm Metrodata Electronics Tbk PT slumped over 11% to hit its lowest since Dec. 3. Philippine financial markets are closed from Monday, Dec. 30, till Wednesday, Jan. 1, for public holidays. Trading will resume on Thursday, Jan. 2. For Asian Companies click; SOUTHEAST ASIAN STOCK MARKETS AS AT 0341 GMT STOCK MARKETS Change on the day Market Current Previous close Pct Move Singapore 3230.89 3226.53 0.14 Bangkok 1579.27 1578.22 0.07 Jakarta 6316.353 6329.314 -0.20 Kuala Lumpur 1615.47 1610.61 0.30 Ho Chi Minh 967.16 963.51 0.38 Change so far in 2019 Market Current End 2018 Pct Move Singapore 3230.89 3068.76 5.28 Bangkok 1579.27 1563.88 0.98 Jakarta 6316.353 6,194.50 1.97 Kuala Lumpur 1615.47 1690.58 -4.44 Ho Chi Minh 967.16 892.54 8.36 (Reporting by Shruti Sonal in Bengaluru; editing by Uttaresh.V)