The instruction comes from the ruling committee of the Central Workers' Party, following a meeting attended by, among other things, the high-ranking politician Kim Yo-Jong, sister of the dictator Kim Jong-Un.
The reason why contacts with the neighboring country are broken is said to be "hostility" from South Korean, writes KCNA.
Recently, a series of hateful statements have come from North Korea since defectors in the south sent regime-critical leaflets across the border with the help of balloons.