Seoul, June 22 (AHN) South Korean stocks finished at an all-time high on Monday on a continued rally in semiconductor shares amid signs of progress in US-Iran talks to end their monthslong war in the Middle East. The local currency lost against the US dollar.

After opening 1.08 percent lower, the benchmark Korea Composite Stock Price Index (KOSPI) added 62.13 points, or 0.69 percent, to 9,114.55 after rising as high as 9,253.00, reports Yonhap news agency.

Trade volume was moderate at 377.2 million shares worth 41.4 trillion won (US$26.9 billion) with losers outnumbering winners 739 to 148.

Retail investors and institutions were net buyers, purchasing 2.15 trillion won and 308.4 billion won, respectively, while foreign investors sold a net 2.55 trillion won.

On Sunday, Washington and Tehran wrapped up their first talks and agreed on a road map to reach a final deal within 60 days, according to a statement issued by the mediating countries of Qatar and Pakistan.

The negotiations had been at risk of breakdown as Tehran said it had closed the Strait of Hormuz and U.S. President Donald Trump had repeated his threats to resume attacks on Iran.

"Negotiations went smoothly in general despite some aggressive messages, which were considered short-lived noises," said Kang Jin-hyeok, an analyst from Shinhan Securities.

Semiconductor shares ended in positive territory.

Chip giant SK hynix jumped 5.61 percent to 2.92 million won, surpassing Samsung Electronics in terms of market capitalization for the first time.

SK Square, the parent of SK hynix, surged 10.67 percent to 1.97 million won, and Hanmi Semiconductor, a leading chip manufacturing equipment provider, increased 2.2 percent to 301,500 won.

Defence giant Hanwha Aerospace advanced 0.27 percent to 1.13 million won, and Korea Aerospace Industries (KAI) climbed 1.43 percent to 148,600 won.

However, Samsung Electronics dropped 0.14 percent to 353,500 won, and Samsung Electro-Mechanics, an electronic components manufacturing affiliate of Samsung Electronics, lost 1.85 percent to 2.23 million won.

Top carmaker Hyundai Motor decreased 5.22 percent to 581,000 won, and leading battery maker LG Energy Solution dipped 4.7 percent to 385,500 won.

Samsung Life Insurance slid 9.36 percent to 450,500 won, and pharmaceutical giant Samsung Biologics retreated 5.75 percent to 1.3 million won.

The Korean won was quoted at 1,537 won against the U.S. dollar, down 10 won from the previous session.

Bond prices, which move inversely to yields, closed lower. The yield on three-year Treasurys rose 2.6 basis points to 3.810 percent, and the return on the benchmark five-year government bonds added 3.9 basis points to 4.044 percent.