South Korean stocks retreated Friday as the US Federal Reserve chief signaled interest rates would be aggressively raised. The Korean won fell against the US dollar.

The benchmark Korea Composite Stock Price Index (Kospi) fell 23.5 points, or 0.86 percent, to close at 2,704.71 points. The key stock index gained 0.32 percent from a week ago.

Daily trading volume was moderate at about 1.21 billion shares worth some 11.9 trillion won ($9.6 billion), with losers outnumbering gainers 550 to 313.

Institutions sold a net 699 billion won and foreigners offloaded 155 billion won, while retail investors bought 838 billion won.

Stocks got off to a lackluster start, tracking overnight Wall Street losses. The tech-heavy Nasdaq composite shed more than 2 percent, and the Dow Jones Industrial Average dropped some 1 percent.

Fed Chair Jerome Powell has signaled the US central bank will have to move more aggressively to counter inflation.

The market is expecting the Fed may raise its policy interest rates by 0.5 percentage point in May, the steepest hike since 1982.

Powell said the rate hike by such a margin is an open option in order to reign in the high price pressure.

"Powell's remark strengthened the consensus about raising 50-basis point hike, pulling down the investor sentiment on the Kospi," Shinhan Investment Corp. researcher Choi Yoo-joon said.

Investors seem to be worried that the US tapering move may trigger the capital outflow from the emerging markets, he added.

In Seoul, tech, usually more sensitive to borrowing costs, led the overall market decline.

Market behemoth Samsung Electronics lost 1.03 percent to 67,000 won, with No. 2 chipmaker SK hynix decreasing 2.21 percent to 110,500 won.

Internet portal operator Naver moved down 3.07 percent to 300,000 won, and top carmaker Hyundai Motor shed 1.64 percent to 180,000 won. Bio heavyweight Samsung Biologics slid 0.62 percent to 801,000 won.

The local currency closed at 1,239.1 won against the US dollar, down 0.1 won from the previous session's close. (Yonhap)