The assembly, which takes formal steps to adopt policy decisions of the ruling Workers' Party, also voted to abolish laws governing economic ties with Seoul, including the special law on the operation of the Mount Kumgang tourism project.
The tours to the scenic mountain just north of the eastern border were a symbol of economic cooperation that began during a period of engagement between the two Koreas in early 2000s, drawing nearly 2 million South Korean visitors.
The project was suspended in 2008 after a South Korean tourist who strayed into a restricted zone was shot and killed by North Korean guards.
Hyundai Asan, an affiliate of the Hyundai Group conglomerate which invested more than 750 billion won ($564 million) in developing the Kumgang project, declined to comment on the report.
South Korea's Unification Ministry, which handles ties with Pyongyang, said the North's action was not surprising and would only deepen its isolation. Seoul does not recognize the unilateral move, an official added.
The KCNA report did not mention the North's special law governing another major joint economic project, the Kaesong industrial zone, which at its peak housed the factories of 125 South Korean companies employing 55,000 North Korean workers.