Southeast Asian shares rose on Wednesday ahead of the U.S. Federal Reserve's January monetary policy statement due later in the day, helped by overnight gains in oil prices, with the Philippines outperforming the region.

U.S. crude surged 3.7 percent on Tuesday after OPEC renewed calls for rival producers to cut supply alongside its members. However, the contract was down 1.24 percent on Wednesday on profit-taking.

The Philippine stock index was up 2.1 percent near a two-week high, led by financials. Thailand gained 1.1 percent on energy shares, while Indonesia rose 0.7 percent on the back of large caps.

"We expect to see a dovish Fed statement as global and China's economic concerns become one of the key factors on rate decision," said Teerada Charnyingyong, an analyst at Phillip Capital in Bangkok.

The Fed's statement will explain the state of the world's largest economy and its stance on interest rate hike in the future. Many expect it to be dovish.

Bank of Japan will hold policy meetings on Jan. 28-29.