Singapore stocks .STI rose as much as 1.2%, largely on the back of major banks. The index has advanced more than 7% this month.
Currencies in emerging Asian economies held their ground as the dollar =USD remained under pressure from fading prospects of a U.S. rate hike this month.
The MSCI gauge of emerging market currencies .MIEM00000CUS inched lower. The Malaysian ringgit MYR= and the Singapore dollar SGD= strengthened marginally, while the Thai baht THB=TH slipped 0.2%.
The South Korean won KRW=KFTC touched a two-month high of 1,484.5 before giving up the gains.
A potentially more hawkish Bank of Korea at Thursday's meeting, continued semiconductor sector strength, and cheap won valuations have partly helped the currency outperform regional peers in recent sessions, Llody Chan, an FX strategist at MUFG, said in a note.
The central bank is expected to raise interest rates for the first time in more than three years on Thursday and deliver another increase by the end of the year, a Reuters poll showed.
Indonesian equities .JKSE gained for a fifth straight day, while the rupiah IDR= traded at a one-week high.
The Indonesia Stock Exchange CEO, Jeffrey Hendrik, said the bourse would add 37 stocks to its list of companies with highly concentrated shareholdings as part of reforms following a warning earlier this year from index provider MSCI MSCI.N.