TOKYO, June 18 (Xinhua) -- Tokyo stocks opened lower Monday as market players were in a risk-off mood amid trade tensions triggered by recent unilateral import tariff moves by the U.S. against China.

As of 9:15 a.m., the 225-issue Nikkei Stock Average dropped 104.50 points, or 0.46 percent, from Friday to 22,747.25.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, lost 12.38 points, or 0.69 percent, to 1,776.66.

Marine transportation, oil and coal product, and mining issues comprised those that declined the most in the opening minutes after the morning bell.