North Korea's state-run media have been playing a new hymn dedicated to the country's leader Kim Jong-un in an apparent effort to reinforce his personality cult and justify the regime's hereditary succession of power.

The title of the song, "Onwards toward the final victory," is the last phrase of Kim's speech on April 15, which marked the 100th birth anniversary of his grandfather, the country's founding leader Kim Il-sung.

North Korean media outlets, including the Korean Central Broadcasting Station and Radio Pyongyang, have been playing the hymn several times a day since the Rodong Sinmun, the mouthpiece of the North's ruling Workers' Party, published the score on its front page last Tuesday.

The broadcasts claim the song is gaining popularity across the nation and generating enthusiastic responses from soldiers, workers and college students.

It is the first time North Korea has publicly promoted a propaganda song written for Kim since the young leader in his late 20s took power following his father's death in December.

Another song titled "Footsteps" was released in 2009 in honor of the then heir apparent. (Yonhap News)