South Korean stocks retreated for a second straight session Monday as investors took to the sidelines ahead of the US Federal Reserve's policy meeting later this week.

The Korean won rose against the US dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) lost 8.57 points, or 0.28 percent, to close at 3,001.66 points.

Trading volume was moderate at about 368 million shares worth some 8.5 trillion won ($7.2 billion), with losers outnumbering gainers 495 to 347.

Foreigners sold a net 137 billion won, and retail investors offloaded 365 billion won, while institutions bought 468 billion won.

The KOSPI traded bullish in the morning, led by advances by tech and auto heavyweights.

But the key stock index turned to losses toward the session's end.

Investors kept a keen eye for the Federal Reserve's signals about the tapering of stimulus measures. The Fed is set to announce its two-day meeting results Wednesday (US time).

"Stocks are likely to fluctuate without a specific direction until the results of the FOMC meeting are revealed," said Meritz Securities analyst Lee Jin-woo.

In Seoul, market bellwether Samsung Electronics edged down 0.13 percent to 76,800 won, while No. 2 chipmaker SK hynix increased 0.83 percent to 121,500 won.

Internet portal operator Naver lost 1.14 percent to 390,500 won, and its rival Kakao decreased 2.04 percent to 120,000 won.

Among gainers, leading carmaker Hyundai Motor moved up 0.72 percent to 209,000 won, with its smaller affiliate Kia adding 0.7 percent to 86,000 won. LG Electronics soared 6.35 percent to 134,000 won.

The local currency closed at 1,180.8 won against the US dollar, up 0.5 percent from the previous session's close. (Yonhap)