North Korea has announced that it is printing "anti-enemy" leaflets in large numbers and preparing to send them across the border to South Korea.

The North's official Korean Central News Agency (KCNA) said Saturday that enraged North Koreans are pushing to distribute the anti-Seoul leaflets, and that publishing agencies are rushing to print them so they can indiscriminately attack South Korean authorities.

It said the leaflets detailing the offenses of South Korean authorities were piling up like a mountain.

The KCNA also released several photos showing North Korean workers, wearing masks, printing and sorting bundles of leaflets.

Seoul's Unification Ministry on Saturday urged Pyongyang to "immediately" withdraw its plans to send leaflets across the border.

Sending its own propaganda leaflets to South Korea was one of the measures Pyongyang vowed to take on Wednesday in a statement issued by the General Staff of the North's Korean People's Army, which also warned of military action.