The Tokyo Shimbun said North Korean leader Kim Jong-un reached the decision to secure a 1 million ton petroleum stockpile during a meeting of the State Affairs Commission in April.

The targeted amount accounts for about half to two-thirds of the North's annual imports of crude oil and petroleum products, it noted. North Korea is known to import about 1.5 million to 2 million tons of crude and petroleum products a year, with over 90 percent shipped from China.

Following the April decision, said the newspaper, the number of gas stations closed in Pyongyang skyrocketed, resulting in a surge in oil prices.

Oil prices in the North somewhat stabilized for some time later but began to move upwards recently, raising speculation that authorities there are artificially restricting the supply of petroleum into the market.

Even ranking officials in Pyongyang are given a substantially limited ration of automobile fuel and must depend on private vendors to commute to work, the newspaper reported.

The North recently decided to cancel an international air show slated for Sept. 23-24 in Wonsan on the east coast, in an apparent move to avoid the waste of aviation fuel in the face of toughening sanctions by the United Nations Security Council over its repeated nuclear and missile provocations.

The Japanese government is reportedly persuading the international community to slap additional sanctions, including a ban on North-bound oil exports, in retaliation for its firing of a ballistic missile over Japan in late August. (Yonhap)