TOKYO, March 2 (Xinhua) -- Tokyo stocks opened sharply lower Friday on renewed concerns over U.S. protectionism after President Donald Trump said he will impose new tariffs on steel and aluminum imports.

As of 9:15 a.m. local time, the 225-issue Nikkei Stock Average tumbled 479.83 points, or 2.21 percent, from Thursday to 21,244.64.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, fell 29.38 points, or 1.69 percent, at 1,710.82.

On the main section all industry categories retreated, with iron and steel, precision instrument and marine transportation-linked issues comprising those that declined the most in the opening minutes after the morning bell.