South Korean stocks jumped as risk appetite improved after President Donald Trump said the US was nearing an agreement with Iran to end the war.  

Chip stocks paced the gains in the benchmark Kospi Index, which surged as much as 8% early morning. 

Friday’s rally again demonstrated the wild swings that has become a hallmark of South Korea’s $4.3 trillion equity market. Korea Exchange briefly halted program buying in Kospi as futures surged. Korean stocks were among the biggest winners in the region on Friday after Trump abruptly pulled back threatened military strikes against Iran, sparking a rally in Wall Street and risk assets more broadly.

Samsung Electronics Co. and SK Hynix Inc shares each surged more than 9% as investors returned to the stocks that are seen as the critical to the AI rollout. 

Market volatility has intensified in recent months as more than half of the Kospi’s market capitalization is concentrated in Samsung and SK Hynix. The growing popularity of leveraged exchange-traded funds linked to the two chipmakers, which amplify daily price moves, has also contributed to larger market swings.

“The fundamental outlook and the structural strength of Korea’s tech suggest that the position of Korea’s role in memory semiconductors is hard to be replaced anytime soon,” said Indrani De, global head of investment research at FTSE Russell. “Samsung and SK Hynix dominate the high bandwidth memory market,” she added.

Korea Exchange triggered market safeguards repeatedly this week, including a 20-minute circuit breaker on Monday, as Korean stocks lurched from one extreme to another.

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Published on June 12, 2026