South Korean stocks started weaker Tuesday as investors take a cautious approach ahead of a US rate-setting meeting later this week.

The benchmark Korea Composite Stock Price Index added 2.56 points, or 0.1 percent, to 2,577.28 in the first 15 minutes of trading.

Overnight, US stocks also closed little changed. The Dow Jones Industrial Average grew 0.02 percent, the tech-heavy Nasdaq Composite inched up 0.01 percent, and the S&P 500 rose 0.07 percent.

The Federal Reserve will hold the Federal Open Market Committee for two days starting Tuesday and is expected to keep rates on hold.

But the market expects the US central bank may deliver one more rate hike this year, given the solid economic recovery of the world's largest economy.

In Seoul, big-cap stocks traded mixed.

Samsung Electronics, the No. 1 memory chipmaker in the world, gained 0.43 percent and its rival SK hynix jumped 1.43 percent.

Steel giant Posco Holdings advanced 0.17 percent and its chemical materials unit Posco Future M climbed 0.61 percent.

Top carmaker Hyundai Motor added 0.16 percent, but its smaller affiliate Kia dipped 0.13 percent and its auto parts-making affiliate Hyundai Mobis dropped 0.64 percent.

Leading chemical producer LG Chem retreated more than 1.5 percent.

Battery shares, including LG Energy Solution and Samsung SDI, were flat.

The local currency was trading at 1,321.30 won against the US dollar at 9:15 a.m., up 3.1 won from Monday's close. (Yonhap)