South Korean stocks opened steeply lower Tuesday, tracking a US stock plunge that stemmed from concerns that the resurgence in the new coronavirus and its variants may hamper the ailing global economy.

The benchmark Korea Composite Stock Price Index (Kospi) slumped 18.44 points, or 0.57 percent, to 3,225.6 points in the first 15 minutes of trading.

Virus worries continued to pull down the Kospi after the key stock index's 1 percent retreat the previous session.

Overnight, the big-three US stock indexes tumbled, with the Dow Jones Industrial Average declining 2.09 percent. The tech-heavy Nasdaq Composite and the S&P 500 were down 1.06 percent and 1.59 percent, respectively.

South Korea's new daily cases have reached more than 1,000 for two weeks, prompting authorities to tighten virus curbs across the nation ahead of the summer holiday season.

Most large caps opened lower in Seoul, while bio heavyweights advanced.

Market kingpin Samsung Electronics shed 0.63 percent, and No. 2 chipmaker SK hynix retreated 0.42 percent.

Internet portal giant Naver moved down 0.68 percent, and leading carmaker Hyundai Motor declined 0.66 percent. Giant chemical maker LG Chem lost 0.61 percent.

Top pharmaceutical firm Samsung Biologics edged down 0.22 percent, with Celltrion jumping 2.85 percent.

The local currency was trading at 1,151.8 won to the US dollar, down 4 won from the previous session's close. (Yonhap)