North Korean leader Kim Jong Un has overseen a military drill for the fourth time in two weeks. The move appears to be a show of defiance toward the United States and South Korea.

The ruling Workers' Party newspaper, Rodong Sinmun, reported on Saturday that Kim, accompanied by his daughter, inspected paratrooper drills on Friday.

The exercise involved troops leaping from a transport aircraft to land on a simulated enemy position.

A photograph showed Kim's daughter watching the drill through binoculars.

Kim reportedly stressed the need for all service members to "firmly arm themselves with the strong will against the enemy and thoroughgoing outlook on war that they have to change history without fail if a war breaks out, and continue to spur the war preparations."

The newspaper also carried on its front page a photo-feature of Kim and his daughter attending a ceremony to mark the completion of a vegetable farm in the capital Pyongyang.

Kim praised military personnel who were mobilized to build the farm, calling them "heroic officers" who create "happiness of the people".

South Korea's Yonhap News Agency said the report appears to demonstrate efforts by Kim and his daughter to improve the livelihoods of the people. The agency described Kim's daughter as his possible successor.