TOKYO - As North Korea begins a 10-day period of mourning to mark the 20th anniversary of the death of its first leader, Kim Il Sung, Pyongyang watchers are paying closer attention to his grandson -- who was shown on state media walking to his seat for a memorial event with a noticeable limp.

Kim Jong Un seemed to have somehow hurt his leg enough to require a slight, but visible, limp as he marched across the stage Tuesday to assume his position of honour. He limped again as he left the room when the event was over.

Although the limp appeared relatively minor, it is unusual for the North's state-run media to display images of the leaders that do not depict them as in peak form. The decision to broadcast a limping Kim has been interpreted by some foreign observers as an interesting departure from past precedent.

State media had no comment on the limp, or their decision to broadcast it.