KOSPI surges 7.44% on June 12 after Donald Trump announces Iran settlement
South Korean equity markets experienced a massive rally on Thursday, June 12, 2026, as the benchmark KOSPI index surged 7.44% following optimistic signs of a diplomatic breakthrough between the United States and Iran. U.S.
President Donald Trump fueled the buying spree by stating a “great settlement” had been reached with Tehran, noting that a formal agreement could be signed in Europe as early as the upcoming weekend.
The Seoul-based market reaction was immediate and aggressive. By 9:15 a.m. KST on June 12, the KOSPI had jumped 577.61 points to reach 8,341.56. During the session, the index touched an intraday peak of 8,424, representing an 8.5% rise. This surge cements the index’s position as the world’s top performer in 2026, with a year-to-date climb of 94%.
Investor sentiment was bolstered by the prospect of reduced geopolitical risk and a potential easing of energy-driven inflation. This optimistic outlook caused global stocks to rise and oil prices to fall, creating a favorable backdrop for South Korean exporters. The Korean won also reflected the risk-on mood, trading at 1,521 won against the U.S. dollar, up 7.9 won from the previous session.
Semiconductor heavyweights lead the Korean stocks surge
Samsung Electronics (005930.KS) and SK Hynix (000660.KS) served as the primary engines for the rally. Samsung Electronics shares jumped 12.21% on June 12, following a strong premarket performance on Wednesday where shares rose 9.20% to 326,500 won. The gains were supported by a robust overnight performance in U.S. semiconductor stocks and better-than-expected Producer Price Index (PPI) data for May.
SK Hynix also saw explosive growth, with its stock climbing 8.85% during Thursday morning’s trading. The company’s premarket activity on June 11 had already hinted at the coming surge, with shares rising 9.47% to 2.3 million won. Traders appear to be betting that a stable Middle East will reduce input costs for these manufacturing giants while maintaining high demand for hardware.
While the focus remained on technology, industrial leaders across various sectors participated in the upswing. Many firms are currently finding that supply chain resiliency is increasingly prioritised, and the potential Iran deal offers a rare moment of stability for global logistics. POSCO Holdings rose 6.84%, while LG Electronics and LG Energy Solution gained 6.19% and 6.11% respectively.
Automotive and aerospace sectors see Broad gains
The Korean automotive industry benefited significantly from the improved global outlook. Hyundai Motor shares rose 6.03% on June 12, while Kia Corporation followed with a 4.9% increase. These gains were preceded by strength in the premarket session on June 11, during which Hyundai Motor climbed 6.03% and Hyundai Mobis rose 6.08%.
Defense and energy stocks also saw upward movement despite the move toward a peace settlement. Hanwha Aerospace jumped 5.7%, and Doosan Enerbility rose 5.6%. This broad-based participation suggests that investors are not just rotating into tech but are deploying capital across the entire South Korean industrial spectrum in anticipation of lower energy costs.
Wall Street momentum supports record Seoul performance
The rally in Seoul was further catalyzed by a strong showing on Wall Street the previous evening. On Wednesday, June 11, the Dow Jones Industrial Average rose 1.9%, and the S&P 500 gained 1.8%. The tech-heavy Nasdaq also posted significant gains, providing a “green light” for Asian markets to open sharply higher on Thursday morning.
The KOSPI’s 6.44% opening jump on June 12 was part of a larger trend that saw the index finish the week up 3.2%. Analysts point to the confluence of favorable U.S. inflation data and President Trump’s diplomatic optimism as a rare double-catalyst. Such conditions have allowed the South Korean market to decouple from other regional peers that remain hampered by local economic concerns.
While the market has reached record territory, all eyes are now on the European summit where the final Iran deal is expected to be signed. Any delay or failure to finalize the “great settlement” mentioned by President Trump could result in a sharp reversal of these gains.
For now, the momentum remains firmly behind Samsung and the wider KOSPI ecosystem as the week draws to a close.