South Korean stocks opened lower Thursday following overnight losses on Wall Street after U.S. Federal Reserve Chair Janet Yellen hinted at an interest rate hike this month.

The benchmark Korea Composite Stock Price Index lost 13.11 points, or 0.65 percent, to 1,996.1 in the first 15 minutes of trading.

Stocks fell across the board, with chemicals leading the losses.

SK Innovation, the nation's top refiner, declined 1.57 percent, and No. 3 S-Oil retreated 1.74 percent.

U.S. stocks fell on Wednesday after Yellen said she was "looking forward" to a U.S. interest rate rise that will be seen as a testament to the economy's recovery from recession.

The local currency was trading at 1,166.3 won against the U.S. dollar as of 9:15 a.m., down 2.0 won from Wednesday's close. (Yonhap)