Seoul, May 4 (AHN) South Korean stocks shot up by more than 5 per cent to close at a fresh high on Monday, approaching the 7,000-point mark, as investors scooped up semiconductor shares while awaiting developments in US-Iran peace talks. The Korean won rose sharply against the US dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) added 338.12 points, or 5.12 percent, to a fresh record high of 6,936.99.

Trade volume was heavy at 864.3 million shares worth 41.3 trillion won (US$28.2 billion), with losers outnumbering winners 473 to 392, reports Yonhap news agency.

Foreigners bought 3 trillion won worth of local shares, and institutions purchased a net 1.9 trillion won, while retail investors dumped a net 4.8 trillion won.

The index opened 2.79 percent higher after U.S. President Donald Trump announced a plan to guide ships not involved in the Iran conflict through the Strait of Hormuz as a "humanitarian gesture" starting this week.

Later, a senior Iranian official warned that Tehran would consider any U.S. interference in the strait a ceasefire breach.

However, the KOSPI extended its gains in the afternoon, supported by foreign and institutional buying.

"Tech shares were driven by gains on Wall Street over the weekend," Lee Kyung-min, an analyst at Daishin Securities, said. "Also, foreign investors expanded their net purchase ahead of the market closure for Children's Day on Tuesday."

The main index surpassed the 5,000-point mark in late January and topped another milestone of the 6,000-point level in February.

After recouping its losses in March following the outbreak of the U.S.-Iran war in late February, the KOSPI is now approaching the uncharted 7,000-point level on continued optimism over the AI boom and hopes for the reopening of the key waterway.

Semiconductor stocks led the rally. Chip giant Samsung Electronics jumped 5.44 percent to 232,500 won, and its chipmaking rival SK hynix surged 12.52 percent to a fresh record high of 1.4 million won, surpassing 10 trillion won in market capitalization for the first time.

Hanmi Semiconductor, a chip equipment manufacturer, rose 2.72 percent to 378,000 won, and Samsung Electro-Mechanics, an electronic components affiliate of Samsung Electronics Co., soared 10.34 percent to 918,000 won.

Defence shares were also strong as industry leader Hanwha Aerospace advanced 3.39 percent to 1.4 million won and LIG D&A gained 4.46 percent to 983,000 won.

Top carmaker Hyundai Motor climbed 1.51 percent to 539,000 won, and leading battery maker LG Energy Solution increased 2.5 percent to 472,000 won.

However, bio shares went south as Celltrion fell 1.35 percent to 197,800 won, and Samsung Biologics dropped 2.58 percent to 1.4 million won.

The Korean won was quoted at 1,462.8 won against the U.S. dollar at 3:30 p.m., up 20.5 won from the previous session.

The quotation marks the highest since February 27, when the currency closed at 1,439.7 to the greenback.

Bond prices, which move inversely to yields, closed lower. The yield on three-year Treasurys added 2 basis points to 3.615 percent, while the return on the benchmark five-year government bonds gained 1.7 basis points to 3.797 percent.