The benchmark Korea Composite Stock Price Index(KOSPI) tumbled along with world stock markets after President Donald Trump said the United States would impose tariffs of 25 percent on steel and ten percent on aluminum imports. 

The main bourse lost 25-point-two points, or one-point-04 percent, on Friday on concerns of a potential trade war to close at two-thousand-402-point-16. 

The tech-heavy KOSDAQ rose three-point-17 points, or point-37 percent, ending the day at 860-point-23. 

On the foreign exchange, the local currency strengthened two-point-five won against the dollar, ending the session at one-thousand-80-point-three won.