Seoul shares sink over 5 pct on tech losses amid Iran uncertainty; won sharply down

SEOUL, June 5 (Yonhap) -- South Korean stocks dipped by more than 5 percent as investors locked in profits from a recent tech-led rally while monitoring uncertainty over U.S.-Iran peace negotiations. The local currency weakened sharply against the U.S. dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) lost 478.82 points, or 5.54 percent, to close at 8,160.59, retreating for a second consecutive session.

After opening 3.44 percent lower, the Korea Exchange suspended program trading for the KOSPI for five minutes at 9:08 a.m., triggering a sidecar after the KOSPI 200 Futures index fell 5 percent or more for at least one minute.

The Dow Jones Industrial Average rose 1.73 percent, and the S&P 500 added 0.41 percent to 7,584.31. The tech-heavy Nasdaq composite slipped 0.09 percent as declines in stocks related to artificial intelligence (AI) weighed on the index.

Broadcom tumbled more than 12 percent after the U.S. chipmaker's quarterly results, and outlook for AI-related revenue fell short of investors' lofty expectations.

Oil prices retreated after three consecutive sessions of gains as investor sentiment improved following reports that Israel had agreed to a conditional ceasefire with Lebanon.

In Seoul, most large-cap stocks ended lower as foreign investors extended their selling streak to a 20th consecutive session.

The Korean won was quoted at 1,539.1 won against the U.S. dollar at 3:30 p.m., down 9.4 won from the previous session.

A dealing room at Hana Bank in Seoul on June 5, 2026 (Yonhap)