The top leader of the Democratic People's Republic of Korea (DPRK) has called for strengthening the first-line units in the southern border and turning the border line into an "impregnable fortress," the official Korean Central News Agency (KCNA) said Monday.

Kim Jong Un, general secretary of the Workers' Party of Korea and president of the State Affairs of the DPRK, made the remarks at a meeting of commanding officers from divisions and brigades of the entire army on Sunday.

During the meeting, Kim outlined a policy to readjust the training system and intensify practical training in line with the changing aspects of modern warfare and the development trend of the country's armed forces, the KCNA report said.

Kim also stressed the importance of redefining the concept of operations across all spheres in line with the rapid modernization of the army's military and technical equipment, and applying it to the combat training of units.