The announcement, which came amid an intensifying US-China trade dispute, put Korea at risk of higher tariffs, alongside the world’s second-largest economy China, Japan, India, Germany, and Switzerland.
The benchmark Kospi closed 14.28 points, or 0.69 percent, lower at 2,045.31.
Friday’s closing marked the lowest point since Jan. 8, when the index stood at 2,025.27. Foreign investors net sold 329 billion won worth of local stocks, extending a weeks-long dumping spree.
The secondary tech-heavy bourse Kosdaq also shed 6.86 percent or 0.98 percent lower at 690.03.
The local stock market opened lower, tracking losses on Wall Street overnight.
The local currency closed at 1,188.40 won against the US dollar, up 0.80 won from the previous session’s close.
“Concerns of a prolonged US-China trade war dragged down the local market, and the US Commerce Departments proposal of a new rule to impose anti-subsidy duties on countries it claims undervalue their currencies against the dollar worked as a negative factor,” Seo Sang-young, an analyst at Kiwoom Securities said.
The Ministry of Economy and Finance did not release any statement addressing the US Commerce Department’s remarks as of the market’s closing.