Kuwait became Japan's third-biggest crude oil supplier in April, providing 7.71 million barrels, or 257,000 barrels per day (bpd), government data showed.
But Kuwait's crude oil exports to Japan fell 10.5 percent from a year earlier, down for the third consecutive month, the Japanese Natural Resources and Energy Agency said in a preliminary report, Kuwait News Agency (KUNA) reported.
It supplied 7.3 per cent of the Asian country's total crude imports to overtake Qatar.
Japan's overall imports of crude oil increased 1.8 per cent year-on-year to 3.53 million bpd, the first expansion in three months. 
Shipments from the Middle East accounted for 84.0 per cent of the total, down 3.6 percentage points from the previous year.
Saudi Arabia remained Japan's No.1 oil provider, but imports from the kingdom slid 2.6 per cent from a year earlier to 1.39 million bpd, followed by the United Arab Emirates with 833,000 bpd, up 24.0 per cent. Qatar ranked fourth with 247,000 bpd and Russia fifth with 220,000 bpd, respectively.
Japan is the world's-third biggest consumer of oil after the US and China.

Source: BNA