South Korean stocks ended almost flat on Wednesday as the prolonged currency volatility and North Korea's threat for a nuclear test continued to weigh down the market, analysts said. The local currency fell against the U.S. dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) shed 0.1 percent, or 1.99 points, to 1,936.19. Trading volume was moderate at 342.9 million shares worth 3.5 trillion won (US$3.3 billion) with gainers outpacing losers 461 to 338.

"Despite the gains on Wall Street overnight, the local stock market closed almost flat due to the continued concerns over a weaker yen," said Bae Sung-young, an analyst at Hyundai Securities Co.

"Local exporters, including carmakers, lost their price competitiveness as they are in direct competition with Japanese firms," Bae added. "The North Korea's threats also weighed down investor sentiment."

North Korea vowed last month to conduct its third nuclear test in response to the U.N. Security Council resolution tightening sanctions against it as punishment for its December rocket launch.

Foreigners offloaded a net 88.8 billion won worth of local shares, and institutional investors dumped a net 8.6 billion won.

Meanwhile, retail investors scooped up a net 104.4 billion won.

Carmakers continued to fall on the appreciation of the local currency against the Japanese yen, with No. 1 player Hyundai Motor losing 1.97 percent to 199,500 won and its smaller affiliate Kia Motors moving down 2.06 percent to 49,950 won.

NHN, the operator of South Korea's most visited Web portal, declined for a third consecutive session plunging 2.16 percent to 226,500 won.

Dongkuk Steel Mill, South Korea's third-largest steelmaker, fell 3.56 percent to 12,200 won after the firm said Tuesday that it swung to a net loss in 2012 due to decreased sales and falling steel prices.

On the other hand, Doosan Infracore Co., South Korea's leading construction equipment maker, edged up 0.97 percent to 15,650 won on the market outlook that the firm's earnings will gradually improve this year.

Flat panel giant LG Display moved up 3.25 percent to 28,550 won as foreign investors scooped up its shares. Meanwhile, market behemoth Samsung Electronics shed 0.56 percent to 1,427,000 won.

Dohwa Engineering, a local builder, advanced by its daily permissible limit of 14.99 percent to 5,830 won after a South Korean consortium, led by the state-run Korea Water Resources Corp., has been tapped as the priority negotiation partner for water management projects being pushed in Thailand.

The local currency closed at 1,088.10 won against the greenback, down 1.10 won from Tuesday's close, following the rising tension with North Korea, dealers said. (Yonhap News)