South Korea's Stock Market Drops 11% in a Matter of Minutes, Triggering Circuit Breaker

Market Update: Asia Stocks Plummet Amid US-Iran Military Conflict

March 4, 2026

The KOSPI benchmark stock index in South Korea experienced a significant decline, falling 8% and triggering circuit breakers, which halted trading for 20 minutes. The index extended losses to 11% just minutes after the initial drop, marking the first time since August 2024 that circuit breakers were activated on the index.

The KOSPI has suffered a substantial decline of 14% in the last three sessions, while Japan's Nikkei slid 2.5% in a third straight session of losses. Both Japan and South Korea are major energy importers, exacerbating concerns over the potential disruption in oil supplies. Benchmark Brent crude oil futures rose by more than 12% for the week, reaching $81.40 a barrel, although they retreated from highs following the US President's announcement of an insurance guarantee on Gulf shipping and the possibility of naval escorts for oil tankers through the Strait of Hormuz.

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The ongoing US-Iran military conflict has led to increased tensions, with US and Israeli forces pounding Iran for four days, and Iranian drones and missiles striking Gulf oil refineries and US embassies in Saudi Arabia and Kuwait. As a result, gold fell by approximately 4.5% overnight, and the Aussie dollar slid by 0.8% as traders cashed out of winning bets to cover losses elsewhere.

In early trading, gold steadied at $5,128 an ounce, while US and European futures attempted to stabilize, with S&P 500 futures remaining flat and European futures rising by 0.8%. On Wall Street, indexes pared heavier losses, but the S&P 500 closed 0.8% lower due to concerns over potentially prolonged higher oil prices.