BANGKOK, Aug 23 (Reuters) - Indonesian stocks pared gains to end flat on Friday, posting their biggest weekly loss in almost two years, amid caution over the implementation of the recent economic measures, while other markets in Southeast Asia retreated on late selling. Jakarta's Composite Index gained as much as 1.6 percent in morning trade before the government and central bank announced measures aiming at lifting its economy, including cutting the current account deficit. Investors cashed in on earlier gains in large cap stocks, including Bank Mandiri, the second-most actively traded stock, and Astra International, the biggest firm by market value. The benchmark index lost 8.7 percent on the week, its worst since September 2011. "The announcement of economic policy package didn't calm foreign investors and they continued selling in the last hour of trading," said John Teja, director of Ciptadana Securities. The market is cautiously looking forward to the implementation steps from the government to tackle the macro economic concerns, Teja said. Thai stocks were among underperformers in the region, falling 1 percent on the day and 7.5 percent on the week, the largest in five months. Investors sold shares ahead of July exports data due next week for further indication of the health of the economy. Bucking the trend, the Philippine main index edged up 0.4 percent, trimming its loss on the week to 6 percent. The market is shut on Monday, reopening on Tuesday. Stocks in Singapore, Malaysia and Vietnam tumbled more than 3 percent on the week amid the sell-down in the emerging region. 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* 387.64 387.19 +0.12 Singapore 3088.85 3089.40 -0.02 Kuala Lumpur 1721.07 1720.37 +0.04 Bangkok 1338.13 1351.81 -1.01 Jakarta 4169.83 4171.41 -0.04 Manila 6161.21 6136.73 +0.40 Ho Chi Minh 486.82 496.12 -1.87 Change on year Market Current End prev yr Pct Move TR SE Asia Index* 387.64 424.10 -8.60 Singapore 3088.85 3167.08 -2.47 Kuala Lumpur 1721.07 1688.95 +1.90 Bangkok 1388.13 1391.93 -3.87 Jakarta 4169.83 4316.69 -3.40 Manila 6161.21 5812.73 +6.00 Ho Chi Minh 486.82 413.73 +17.67 * The Thomson Reuters South East Asia Index is a highly representative indicator of stocks listed in Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam. Stock Market Volume (shares) Market Current Volume Average Volume 30 days Singapore 278,172,700 272,313,503 Kuala Lumpur 198,357,500 148,127,410 Bangkok 8,615,835 9,391,614 Jakarta 4,104,094,000 3,194,403,717 Manila 79,285 77,765 Ho Chi Minh 54,165 43,440