Seoul stocks slip on fragile US-Iran ceasefire

A stock ticker at Hana Bank headquarters in central Seoul shows the benchmark KOSPI closing at 5,778.01, down 94.33 points, or 1.61 percent, from the previous session, Thursday. Yonhap

Seoul stocks fell Thursday as foreign investors turned cautious over lingering uncertainties surrounding a fragile ceasefire between the United States and Iran, with disagreements persisting over the scope of the truce.

The benchmark KOSPI closed at 5,778.01, down 94.33 points, or 1.61 percent, from the previous session, after opening at 5,826.45 and extending losses as foreign investors led a broad sell-off.

Foreign investors offloaded 873.4 billion won ($589.8 million), weighing on the index, while retail investors and institutions moved to cushion the decline, buying a net 296.1 billion won and 207.7 billion won, respectively.

Market bellwethers also weakened.

Samsung Electronics fell 3.09 percent to 204,000 won, while SK hynix dropped 3.39 percent to 998,000 won.

A similar pattern played out on the tech-heavy Kosdaq, where the index opened at 1083.40, down 0.59 percent from the previous session, and extended losses to close at 1,076.00, down 1.27 percent.

Investor sentiment remained on edge as the two-week ceasefire between the U.S. and Iran showed signs of strain following renewed Israeli strikes on Lebanon, while Tehran warned it could again block the Strait of Hormuz.

Vessels remained stuck in the strategic waterway despite the ceasefire, according to foreign media reports, as the Iranian government said ships must coordinate their movements with the Islamic Revolutionary Guard Corps Navy.

U.S. President Donald Trump said American military forces will remain deployed in and around Iran until Tehran fully complies with the "real agreement," warning that any breach would trigger a large-scale military response.

Markets are expected to remain volatile ahead of weekend talks, as U.S. Vice President JD Vance and other senior U.S. officials are set to travel to Pakistan for mediated negotiations with Iran.

"Short-term volatility is likely to persist depending on the outcome of the weekend talks between the U.S. and Iran. The market is then expected to shift its focus to the earnings season and key economic data," said Seo Sang-young, an analyst at Mirae Asset Securities.

In the foreign exchange market, the Korean won weakened against the dollar, opening at 1,480.6 won and extending losses to close at 1,482.5 won, down 11.9 won from the previous trading day.

Oil prices also edged higher amid ongoing geopolitical concerns. U.S. West Texas Intermediate crude hovered around $97 per barrel, up about 3 percent from the previous day, while Brent crude traded near $96.