North Korea said Saturday it will issue gold and silver coins to mark the 20th anniversary of late leader Kim Jong-il's ascension to the supreme commander of the communist nation's armed forces.

Pyongyang's Korean Central News Agency made the announcement minutes after Kim's successor son, Jong-un, took over the supreme commandership in a strong sign that the young son, believed to be in his late 20s, is rapidly solidifying power.

North Korea also issued stamps with the image of Kim Jong-un, as the communist nation steps up efforts to build a cult of personality around the new leader.

The new stamps were released one day after the official mourning period ended for the country's late leader and father of Kim Jong-un, Kim Jong-il. The senior Kim died of heart failure on Dec. 17, according to North Korean media.

One type of stamp shows an image of Kim Jong-un with his father during a field inspection against the backdrop of Mount Paekdu, and displays the words, "The great leader Kim Jong-il is with us forever," said the North's official Korean Central News Agency.

North Korea claims the mountain is the sacred birthplace of the late leader.

The image is an apparent attempt at justifying the third-generation hereditary transfer of power, as Kim Jong-il has often been depicted with his own father and North Korea founder Kim Il-sung. (Yonhap)