Seoul stocks opened sharply lower on Monday amid renewed energy price concerns after Iran's warning on the Strait of Hormuz. The KOSPI fell 4.72% in the first 15 minutes. The drop comes amid escalating U.S.-Iran tensions.
Seoul stocks opened sharply lower on Monday, March 23, 2026, amid renewed energy price concerns after Tehran warned it could indefinitely close the Strait of Hormuz, a key oil route. The benchmark Korea Composite Stock Price Index (KOSPI) fell 273.11 points, or 4.72 percent, to 5,508.09 in the first 15 minutes of trading. The Korea Exchange issued a sell-side sidecar soon after the opening bell, temporarily halting program trading. Major large-cap stocks traded sharply lower, with market top-cap Samsung Electronics down 5 percent, SK hynix retreating 5.56 percent, top automaker Hyundai Motor falling 4.09 percent, defense giant Hanwha Aerospace shedding 3.86 percent, and KB Financial moving down 4.06 percent. The Korean won traded at 1,503.7 against the U.S. dollar as of 9:15 a.m., down 3.1 won from the previous session. Investor sentiment was dampened as the war in Iran has sent energy prices to record levels, raising inflation concerns and complicating the U.S. Federal Reserve's policy outlook. On Friday, Wall Street's S&P500 fell 1.5 percent and the Nasdaq gave up 2 percent. Fed Governor Christopher Waller signaled a more conservative approach to interest rates in a CNBC interview. Iran issued the warning in response to U.S. President Donald Trump's threat to 'obliterate' Iran's power plants if the Strait was not reopened within 48 hours. The U.S.-Israeli war against Iran entered its fourth week, with the Strait effectively closed following Iranian retaliatory strikes. Separately, President Lee Jae Myung is set to preside over a regular security meeting, the first since taking office in June 2025, with Prime Minister Kim Min-seok, Joint Chiefs Chairman Gen. Jin Yong-sung, and others to assess security measures.
