Singapore shares came off a more than two-and-a-half-year high to trade lower after three straight sessions of sharp gains, with financials accounting for most of the losses.

Asian shares edged up as crude oil futures took back lost ground. MSCI's broadest index of Asia-Pacific shares outside Japan was up 0.1 percent.

Investors continued their policy vigil with the Federal Reserve set to end its two-day meeting on Wednesday, while the European Central Bank meets on Thursday.

At 0620 GMT, the Straits Times Index lost 0.22 percent or 8 points to 3,457. It ended 0.15 percent higher on Tuesday, taking the year-to-date performance to about 20 percent.