North Korean leader Kim Jong Un has attended a memorial service to mark the 30th anniversary of the death of his grandfather Kim Il Sung, who is regarded as the country's founder.

The state-run Korean Central Television reported that the event was held on Monday at Kim Il Sung Square in Pyongyang.

Kim attended the service dressed in black suit. A senior official of the ruling Workers' Party gave a speech hailing the country's hereditary transfer of power over three generations. The official noted that it is a unique tradition of North Korea that the leader's ideology is passed down in the purest and most perfect manner.

Badges bearing only the portrait of Kim Jong Un that were confirmed for the first time last month were viewed as a sign of Kim's confidence in his own rule, which has lasted more than 10 years.

South Korean media said the memorial service was held in a conventional manner, despite speculation that it could be downsized in the face of Kim's accelerating efforts to iconize himself.

Experts say this may be an attempt by Kim to highlight the legitimacy of the hereditary system and to strengthen his own authority.