Japan's consumer prices rose last month for the fourth month in a row, mainly on the back of higher energy costs.

The Internal Affairs Ministry says the Consumer Price Index, excluding fresh food, was up 0.5 percent in December from a year earlier.

The main reason was more expensive crude oil pushing up fuel prices for consumers. Kerosene soared 36 percent from a year earlier, and gasoline was up more than 22 percent.

Electricity bills increased by over 13 percent, marking the sharpest rise in 40 years and nine months.

Overall energy prices surged 16.4 percent for the biggest increase in 13 years and four months.

Ministry officials say that prices will likely be affected by energy costs throughout this year.