Tokyo's key Nikkei index fell three percent in early trade on Monday, ahead of the imposition this week of tariffs announced by US President Donald Trump.
The benchmark Nikkei 225 index shed 3.02 percent, or 1,122.77 points, to 35,997.56, while the broader Topix index was down 2.86 percent, or 78.85 points, to 2,678.40.