North Korea said Tuesday it stopped disabling its Yongbyon nuclear complex this month and will consider restoring the plutonium-producing facility because the U.S. failed, as promised, to remove it from a list of states that sponsor of terrorism.

The move threatens an agreement among the Koreas, the U.S., Japan, Russia and China for the North to abandon its nuclear weapons in return for energy aid and political concessions.

Russia's Foreign Ministry says in a statement Wednesday that the move evokes 'disappointment and concern' and urges Pyongyang to reconsider.

Removing North Korea from the terrorism list is one of the key U.S. concessions in the deal.