Domestic sales of fuel oil increased by 4.8 percent in August from a year before, reaching 19.79 million kiloliters for the first year-on-year increase in two months, according to a preliminary report issued Monday by the Ministry of International Trade and Industry.

The sales bonanza was apparently due to hot weather in eastern and northern Japan that pushed up the use of cars and air conditioners.

While sales of grade C heavy oil for electricity and industrial use were down, sales of naphtha, grade A heavy oil and kerosene were the highest ever for August. Naptha is a crude gasoline used in petro-chemistry and ethylene production, while grade A oil is used for air conditioning. Gasoline sales also hit a new record.

Meanwhile, Japan's crude oil imports rose by 3.8 percent in August on a year-on-year basis to reach 22.61 million kiloliters, with the Middle East accounting for 85.4 percent of the total, the report says.

Affected by continued cuts in oil output by the Organization of the Petroleum Exporting Countries, the average import price of a barrel of crude oil went up $1.83 to $18.5 in August, marking the fifth consecutive month of increase.

Meanwhile, fuel oil production dropped by 4.5 percent to reach 18.9 million kiloliters, marking the fourth consecutive year-on-year decline. Sales of grade C heavy oil, kerosene and light oil sank compared with the previous year.

Fuel oil imports were up 22.2 percent in August from the previous year, reaching 3.34 million kiloliters. Exports, however, dropped 4.2 percent to reach 1.65 million kiloliters.