The Stock Exchange of Thailand index increase, while Singapore stocks led the gains in Southeast Asia, as investors braced for a meeting between US President Donald Trump and Chinese President Xi Jinping at the end of the week.
Trump and Xi are expected to meet on the sidelines of a G20 summit in Argentina on Friday, to discuss contentious trade matters.
"An agreement for talks over dinner suggests a higher level of engagement, which could result in a gentlemen's agreement not to escalate tariffs further," said Wei Liang Chang, a FX strategist with Mizuho Bank.
"(Peter) Navarro, the (US) Administration's most prominent trade hawk, has been pointedly excluded for the Trump-Xi dinner. If anything, this hints at American inclination to promote a conducive environment for talks rather than ruffle feathers."
However, if the meeting does not result in any deals, the US tariffs on US$200 billion goods, introduced in late September, are likely to be raised to a proposed 25% next year from 10%.
The SET index added 8.67 points or 0.53% to 1,630.77, in trade worth 33.74 billion baht. Siam Commercial Bank Plc rose 2.2%, while Airports of Thailand Plc climbed 1.2%.
Singapore stocks led the gains in Southeast Asia with a 1.3% rise, the best since Nov 2, after October factory data beat expectations.
The city-state's October factory output rose 4.3% on year, much higher than a 2.3% growth predicted by a Reuters survey. The growth was mainly attributable to a 15.8% rise in pharmaceutical production.
Gains were dominated by technology stocks, with Venture Corp Ltd gaining 5.2%, while Singapore Airlines Ltd climbed 2.9%.
Philippine shares closed 0.8% higher, with industrials accounting for more than half of the gains.
Aboitiz Equity Ventures Inc surged 11.1%, making it the biggest boost to the benchmark index, while SM Prime Holdings Inc gained 2.2%.
"The (Philippine) market has been strong for the past couple of sessions. The recent fall in crude oil price might be offsetting some of the concerns with regard to inflation in the Philippines," said Charles William Ang, an associate analyst with COL Financial Inc.
Meanwhile, gains in telecommunication services and basic materials helped Malaysian shares close 0.4% higher.
Petronas Dagangan Bhd rose 2.9%, while Maxis Bhd added 2.3%.
Indonesian shares gained 0.3%, aided by financial and material stocks. Bank Central Asia Tbk PT and Bank Mandiri (Persero) Tbk PT rose 0.5% and 1%, respectively.