Tokyo - Japan's trade deficit more than quadrupled to $3.7bn in March, government data showed on Thursday, as a weaker yen inflated import costs.
The monthly trade deficit expanded to ¥362.4bn from the year-before shortfall of ¥81.8bn, finance ministry data showed.
The heavy deficit was still smaller than ¥480bn economists predicted in a poll by the Nikkei business daily.
Exports rose 1.1% to ¥6.27 trillion while imports climbed 5.5% to ¥6.63 trillion.
The yen's average rate was 94.08 to the dollar in March against 81.04 in March 2012, meaning the value of the Japanese currency fell by 16% on year, the data showed.
A lower yen helps exporters but pushes up import bills.
Japan's fuel imports have stayed high as most its nuclear reactors remain off-line since the huge earthquake and tsunami in 2011 sparked the world's worst atomic accident in a generation.