Korean stocks closed lower on Wednesday as investors responded to mixed earnings reports, eyeing upcoming rate decisions in major economies. The local currency weakened against the U.S. dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) lost 4.23 points, or 0.21 percent, to 2,015.4. Trade volume was moderate at 407.86 million shares worth 5.31 trillion won ($4.62 billion), with losers far beating gainers 490 to 305.

Investors stayed cautious while Federal Reserve officials gathered in Washington, D.C., to decide the interest rate, with an announcement due late Wednesday (local time). The Bank of Japan also makes its policy decision on Thursday amid some speculation it could release an additional monetary stimulus scheme.

"The market index lost upward momentum following last week's rally, while investors were buying shares that posted robust earnings in the first quarter," Kwak Hyun-soo, an analyst at Shinhan Investment, said. "Investors are taking a wait-and-see approach ahead of the rate-setting meetings in the United States and Japan."

Foreigners and retail investors each bought a net 146.02 billion won and 90.31 billion won, while institutions dumped a net 234.33 billion won.

Auto shares were among the biggest losers on downbeat outlook amid a prolonged economic slowdown.

Leading automaker Hyundai Motor declined 2.93 percent to 149,000 won following lackluster first-quarter earnings on tepid demand in emerging markets. Its sister company Kia Motors slipped 1.61 percent to 48,950 won, although its net profit increased 4.6 percent thanks to strong demand for its SUVs and new models.

Top market cap Samsung Electronics edged down 0.31 percent to 1,300,000 won ahead of its earnings release on Thursday.

LG Display, the world's largest flat panel maker, dropped 3.86 percent to 24,900 won as its net profit plunged 99.8 percent due to falling demand.

LG Household & Health Care, the nation's No. 2 cosmetic maker, gained 1.39 percent to 1,018,000 won after posting stronger-than-expected earnings in the January-March period thanks to brisk sales in China.

The local currency closed at 1,148.3 won against the greenback, up 2.7 won from Tuesday's close. (Yonhap)