South Korean shares opened lower Wednesday, tracking overnight falls on Wall Street, as a key US Fed member hinted at more aggressive monetary tightening.

The benchmark Korea Composite Stock Price Index (KOSPI) had lost 16.52 points, or 0.60 percent, to reach 2,742.68 as of 9:15 a.m.

Overnight, the US stock market tumbled, after Federal Reserve Gov. Lael Brainard said the Fed would begin rapidly reducing its balance sheet in May and is preparing for "stronger" actions to bring down inflation. The Dow Jones Industrial Average declined 0.8 percent, and the Nasdaq composite skidded 2.26 percent.

Also, Shanghai's extended lockdown amid soaring virus cases is feared to disrupt global supply chains.

On the Seoul bourse, most big-cap shares traded lower, with tech and chemicals leading the fall.

Market bellwether Samsung Electronics fell 0.72 percent, and No. 2 chipmaker SK hynix sank 1.72 percent.

Major battery maker LG Energy Solution lost 1.78 percent, and Samsung SDI went down 0.83 percent. LG Chem decreased 0.56 percent.

Carmakers also lost ground. Top automaker Hyundai Motor shed 0.84 percent, and its affiliate Kia declined 1.08 percent.

The local currency was trading at 1,219.30 won against the US dollar, down 6.6 won from the previous session's close. (Yonhap)