South Korean stocks closed slightly lower after choppy trading Wednesday as investors took to the sidelines amid lingering concerns of early post-pandemic inflation.

The Korean won rose against the US dollar. The benchmark Korea Composite Stock Price Index (KOSPI) fell 2.89 points, or 0.09 percent, to close at 3,168.43 points.

Trading volume was moderate at about 1.3 billion shares worth some 13 trillion won ($11.6 billion), with gainers outnumbering losers 515 to 337.

Foreigners sold a net 31 billion won, while institutions purchased 282 billion won. Retail investors offloaded a net 239 billion won.

Stocks opened with mild gains despite the overnight losses on Wall Street, as local economists increasingly speculate that the central bank may raise its 2021 growth forecast to some 4 percent this week.

A strong 41.1 percent jump in April exports fanned such optimism, along with brokerage forecasts for an increase in global demand for chips and autos.

But stocks lost ground after briefly touching the 3,180-point level, as investors look to lock in profits from the stock price hike before more signs of early inflation kick in in the markets.

"Investors seem to be taking their time until the personal consumption expenditures (PCE) price index comes out. (The PCE) has been a significant gauge for the Fed," Mirae Asset Securities analyst Seo Sang-young said.

The US Commerce Department is set to release the latest PCE on Friday (US time).

Large caps closed mixed in Seoul, with top cap Samsung Electronics slipping 0.13 percent to 79,800 won and No. 2 chipmaker SK hynix finishing unchanged at 123,000 won.

Internet portal operator Naver moved up 1.4 percent to 363,000 won, while pharmaceutical giant Samsung Biologics shed 1.76 percent to 835,000 won.

Leading chemical firm LG Chem plunged 6.73 percent to 832,000 won, following its announcement to voluntarily replace the lithium-ion batteries used in energy storage systems (ESS) over potential fire risks.

Top automaker Hyundai Motor declined 1.76 percent to 223,500 won.

The local currency closed at 1,116.9 won against the US dollar, up 5.1 won from the previous session's close. (Yonhap)