South Korean stocks fell Friday morning after Iran's new leader vowed to maintain the blockade of the Strait of Hormuz, causing global crude prices to fluctuate around the $100 level. The KOSPI index dropped sharply at the open but trimmed losses later while staying in negative territory. Disruptions at the key Middle East waterway persist despite U.S. President Donald Trump's claim that the war is nearing an end.
On March 13, 2026, Mojtaba Khamenei, Iran's new leader succeeding his father, vowed to keep the Strait of Hormuz closed and warned of stern actions against the U.S. and Israel. The strait handles about 20 percent of global oil shipments. Brent crude, the international benchmark, surpassed $100 per barrel, while U.S. West Texas Intermediate reached $95.73. Prices showed extreme volatility before swinging back to the $100 level.
In Seoul, the Korea Composite Stock Price Index (KOSPI) opened sharply lower, falling 132.95 points, or 2.38 percent, to 5,450.30 as of 9:15 a.m., following a 0.48 percent decline the previous day. By 11:20 a.m., it had trimmed losses to a 76.62-point, or 1.37 percent, drop to 5,506.63. Overnight, U.S. markets also weakened, with the Dow Jones Industrial Average shedding 1.56 percent to its lowest point this year. The Nasdaq Composite fell 1.78 percent, and the S&P 500 lost 1.52 percent.
Major stocks reflected the pressure: Samsung Electronics slipped 3.19 percent early, later down 1.76 percent, and SK hynix lost 3.12 percent before easing to 1.08 percent. Battery maker LG Energy Solution slid 4.95 percent, and Samsung SDI fell 3.12 percent. Oil refiners weakened, with SK Innovation down 3.7 percent and S-Oil off 2.71 percent. Amid global oil supply disruptions, nuclear power plant builders gained: Daewoo Engineering & Construction soared 24.19 percent, and Hyundai Engineering & Construction added 5.27 percent. Financial firms traded lower, KB Financial falling 0.54 percent and Shinhan Financial losing 1.31 percent. Naver edged up 0.11 percent, while Kakao stayed unchanged at 50,400 won. Korean Air rose 0.41 percent, and Asiana Airlines shed 0.57 percent.
The Korean won traded at 1,488.1 against the U.S. dollar early, down 6.9 won, and later at 1,486.7, down 5.5 won from the previous session.