Seoul: South Korean stocks opened lower Monday as uncertainty over U.S.-Iran peace negotiations intensified following U.S. President Donald Trump's continued threats on Tehran. The benchmark Korea Composite Stock Price Index (KOSPI) fell 124.2 points, or 1.37 percent, to 8,928.2 in the first 15 minutes of trading.

According to Yonhap News Agency, the United States and Iran had initiated negotiations in Switzerland; however, the talks were abruptly halted by Iran after Trump threatened military strikes on the country if Hezbollah continued its attacks on Israel. Tehran had earlier announced its intention to close the Strait of Hormuz in response to Israel's ongoing military campaign in Lebanon against the Iranian-backed Hezbollah militant group. This announcement came despite an interim 60-day deal aimed at halting conflict across all fronts.

In Seoul, major market heavyweights contributed to the weak opening. Market bellwether Samsung Electronics saw a decline of 2.68 percent, while its chipmaking rival SK hynix fell by 0.07 percent. Hyundai Motor, South Korea's leading car manufacturer, retreated by 3.92 percent, and Hanwha Ocean, a prominent shipbuilder, tumbled 7.87 percent. Samsung Electro-Mechanics, an electronic components manufacturing affiliate of Samsung Electronics, also experienced a decrease, falling by 0.93 percent.

The Korean won was trading at 1,530.2 won against the U.S. dollar, marking a decline of 3.2 won from the previous session, as of 9:15 a.m.