* Ringgit gains on higher oil prices * Won turns firmer on S.Korean exporters' demand * Rupiah near 4-week low on month-end corporate dlr bids * Baht around 3-week trough on stocks, bonds outflows (Adds text, updates prices) By Jongwoo Cheon SINGAPORE, March 28 (Reuters) - Most emerging Asian currencies firmed on Monday but gains were capped by caution ahead of U.S. economic data and speeches by Federal Reserve officials this week which could add to the case for more interest rate increases than markets had expected. Malaysia's ringgit was supported by higher oil prices, while the South Korean won reversed earlier losses on month-end corporate demand. Earlier, most regional currencies slid with the Indonesian rupiah hitting a near four-week low on growing dollar demand from importers for month-end payments. The Thai baht slumped to its lowest in about three weeks on stock and bond outflows. St. Louis Fed President James Bullard said in an interview with the Nikkei that the U.S. central bank may raise interest rates in April or June. That followed a slew of remarks of other Fed officials who supported expectations of more tightening. The U.S. economy grew at a 1.4 percent annual rate in the fourth quarter, faster than a previously reported 1.0 percent, the Commerce Department said on Friday. "Fed officials generally looked to share views that they need to maintain a rate hike path given a U.S. recovery," said Jeong My-young, Samsung Futures' research head in Seoul. "That prompted investors to unwind bullish bets on Asian currencies, which they built up after the Fed's March decision. But Asian currencies are unlikely to turn to a depreciating trend as possibilities of an April hike are still very low." The Fed earlier this month halved its interest rate hike expectations to two from four this year. Investors are awaiting U.S. data including non-farm payrolls and manufacturing PMI to see whether the economy is strong enough to bear a series of rate increases. Fed officials such as Chair Janet Yellen and New York Fed President William Dudley speak later this week. WON The won gained as South Korean exporters bought it for month-end settlements, causing stop-loss dollar selling. Earlier, the South Korean currency eased as much as 0.3 percent to 1,173.1 per dollar as traders added dollar holdings on the greenback's broad strength. "Despite growing expectations of more U.S. rate hikes, the won is unlikely to return to a weakening trend unless it depreciates to 1,180," said a South Korean bank trader in Seoul. RUPIAH The rupiah lost 0.7 percent to 13,340 per dollar, its weakest since March 1. The Indonesian currency weakened in non-deliverable forwards (NDFs) markets with its one-month NDFs around a four-week low. The official Jakarta Interbank Spot Dollar Rate, which the central bank introduced in 2013 to manage exchange rate fluctuations, was fixed at 13,323, weaker than the previous 13,250. BAHT The baht slid 0.4 percent to 35.405 per dollar, its weakest since March 10. The Thai currency came under pressure as foreign investors sold stocks and bonds on Friday. Gold importers also bought dollar to purchase the precious metal on dips. Gold dropped to its weakest in a month due to a strong U.S. dollar. Gold is popular among Thai investors, and slides in the precious metal's price often prompts investors to increase holdings in the physical metal or in gold futures. CURRENCIES VS U.S. DOLLAR Change on the day at 0535 GMT Currency Latest bid Previous day Pct Move Japan yen 113.62 113.11 -0.45 Sing dlr 1.3708 1.3715 +0.05 Taiwan dlr 32.6730 32.766 +0.28 Korean won 1165.10 1169.20 +0.35 Baht 35.39 35.26 -0.38 Peso 46.49 46.40 -0.19 Rupiah 13310 13250 -0.45 Rupee 66.75 66.64 -0.17 Ringgit 4.0210 4.0370 +0.40 Yuan 6.5147 6.5150 +0.00 Change so far in 2016 Currency Latest bid End prev year Pct Move Japan yen 113.62 120.30 +5.88 Sing dlr 1.3708 1.4177 +3.42 Taiwan dlr 32.673 33.066 +1.20 Korean won 1165.10 1172.50 +0.64 Baht 35.39 36.00 +1.71 Peso 46.49 47.06 +1.23 Rupiah 13310 13785 +3.57 Rupee 66.75 66.15 -0.90 Ringgit 4.0210 4.2935 +6.78 Yuan 6.5147 6.4936 -0.32 (Additional reporting by Satawasin Staporncharnchai in BANGKOK and KyoungHo Lee in SEOUL; Editing by Kim Coghill)