The benchmark Korea Composite Stock Price Index shed 6.99 points, or 0.3 percent, to 2,319.63 as of 11:20 a.m.
Carmakers lost ground, with Hyundai Motor Co. falling 2.17 percent and its sister Kia Motors moving down 3.81 percent. Hyundai Mobis, the country's largest car parts producer, shed 2.1 percent.
No. 1 mobile carrier SK Telecom backtracked 2.22 percent, and KT stepped down 0.99 percent. LG Uplus, the smallest player in the telecoms market, dropped 3.64 percent.
South Korea's No. 2 chipmaker SK hynix, on the other hand, shot up 2.15 percent.
The local currency was trading at 1,131.50 won against the US dollar, down 0.40 won from the previous session's close. (Yonhap)