Brussels  - The North Atlantic Treaty Organization (NATO) has hit out at the announcement by North Korea Monday that it had conducted a nuclear test explosion, calling the action "irresponsible."

In a statement the military alliance said that the test poses a "serious challenge to peace, security and stability in the Asia- Pacific region and are being universally condemned by the international community."

"This provocative action of Pyongyangs occurs during a period when the international community is seriously debating important new steps in global arms control, disarmament and non-proliferation," the statement added." (dpa)