The Bulletin of the Atomic Scientists made the annual announcement citing threats that include climate change, proliferation of nuclear weapons, instability in the Middle East
The North's official Korean Central News Agency (KCNA) issued the criticism in an article attributed to an international security analyst, following Japan's formal inauguration of an independent mission to NATO last week to bolster cooperation.
US Deputy Secretary of State Kurt Campbell addressed reporters after talks with South Korean and Japanese officials, focusing on revitalizing international pressure against North Korea amid challenges at the UN Security Council.
Analysts say N Korea will likely leverage enlarged nuclear arsenal for US concessions like sanctions relief after a new US administration is inaugurated
North Korea has been pushing to introduce variety of sophisticated weapons systems designed to attack South Korea, mainland US to deal with intensifying security threats
Warning comes after Kim Yo-jong, the influential sister of North Korean leader Kim Jong-un, claims "dirty leaflets and things" discovered in border region