[Digital Today reporter Ji-young Lee (이지영)] South Korea's KOSPI, which set a new intraday record high, gave up gains amid uncertainty over U.S.-Iran talks and ended slightly lower.

The KOSPI on Thursday closed down 11.42 points, or 0.13 percent, at 9,052.42 from the previous session.

After breaking above 9,000 a day earlier, the KOSPI rose to 9,385.59 early in the session but turned lower in the afternoon. Volatility also increased as it slid as low as 8,831.72 at one point.

News that a working-level meeting between the United States and Iran had been postponed weighed on investor sentiment.

By investor type, foreigners and institutions net sold 361.0 billion won and 1.23 trillion won, respectively. Individuals net bought 1.66 trillion won.

Among top market-cap stocks, Samsung Electronics rose as high as 374,500 won during the session to set a new record, but ended down 2.34 percent.

SK Hynix rose as high as 2,891,000 won to set a new intraday record and finished up 2.94 percent.

The Kosdaq ended down 34.34 points, or 3.43 percent, at 966.59. Institutions net sold 585.0 billion won, while individuals and foreigners net bought 77.8 billion won and 487.5 billion won, respectively.

The won ended at 1,527.0 per dollar, up 0.1 won from the previous session.