The government had hoped the price would stabilise when newly harvested rice hit the shelves in the autumn, but the increase continued.
The latest average retail price of a 5kg bag was ¥3,688 (US$24) according to a government survey in February, up from ¥2,023 last year.
In an unprecedented move, the agriculture ministry decided last month to allow the sale of the government’s stockpile of rice under a new rule.
Previously, stockpiled rice could be released only in the event of a serious crop failure or disaster, but a change in regulations allows a release when rice distribution is deemed stagnant.
The ministry has to buy back the same amount of rice from distributors within a year.
The government enacted a law to stockpile rice in 1995 after a major rice crop failure two years earlier sent shoppers scrambling to buy the staple.
