June 24 (Reuters) - Most Southeast Asian stocks fell to multi-month lows on Monday with fears of a tighter monetary policy in China adding to concerns of investors, who have been exiting the region since the U.S. Federal Reserve said it would scale back its stimulus. The Philippines' main index fell 3.4 percent to a near six-month low, the Thai SET index lost 2.6 percent, its lowest close since Dec. 18, and Jakarta's Composite Index closed 1.9 percent weaker to a near five-month low. Fears over policy tightening by China hit sentiment after a warning from the People's Bank of China that local banks needed to do a better job of managing their cash and lending. Foreign investors sold a net $1.95 billion in shares in Jakarta and $1.46 billion in Thailand in the first three weeks of June ended on Friday, Thomson Reuters and bourse data showed. Kuala Lumpur and Manila witnessed foreign outflows of $971 million and $338 million in the same period. Singapore's Straits Times Index fell 1.6 percent to a more than six-month low, led by a 3.1 percent fall in palm oil firm Wilmar International Ltd which has a large exposure to China via its oilseeds crushing and consumer pack businesses. Malaysian shares dropped 1 percent to their lowest since May 3, with foreign outflows at $117.94 million on Monday. Jakarta's broader stock index also fell 1.9 percent to a five-month closing low with foreign outflows of $68.6 million. Vietnam, the region's smallest bourse, lost 1.8 percent to a five-week low on foreign selling in blue chips. For Asian Companies click; For South East Asia Hot Stock reports, click; SOUTHEAST ASIAN STOCK MARKETS Change on day Market Current Prev Close Pct Move TR SE Asia Index* 406.30 415.90 -2.31 Singapore 3074.31 3124.45 -1.60 Kuala Lumpur 1738.19 1755.85 -1.01 Bangkok 1364.09 1400.50 -2.60 Jakarta 4429.46 4515.37 -1.90 Manila 5971.05 6182.17 -3.41 Ho Chi Minh 489.74 498.84 -1.82 Change on year Market Current End prev yr Pct Move TR SE Asia Index* 406.30 424.10 -4.20 Singapore 3074.71 3167.08 -2.93 Kuala Lumpur 1738.19 1688.95 +2.92 Bangkok 1364.09 1391.93 -2.00 Jakarta 4429.46 4316.69 +2.61 Manila 5971.05 5812.73 +2.72 Ho Chi Minh 489.74 413.73 +18.37 * The Thomson Reuters South East Asia Index is a highly representative indicator of stocks listed in Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam.