Under the treaty, there are five countries recognised as nuclear weapon states, and these correspond with the five permanent members of the United Nations Security Council with veto powers: The United States of America; Russia; United Kingdom; France and China. All other countries under the treaty are non-nuclear weapon states.
However, several other countries have acquired nuclear weapons outside of the provisions of the NPT. These countries include India, Pakistan and North Korea. Another country of interest is Israel which has a policy of 'neither denying nor affirming' its nuclear weapons status. But it is widely believed that Israel posesses nuclear weapons.
Article VI of the 1968 Treaty provides:
'Each of the Parties to the Treaty undertakes to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control.'
Already, measures and talks aimed at disarmament ave been undertaken between the USA and Russia, but at the same time, new and heavy investments by these and other countries in nuclear weapons seem to counter any moves towards disarmament. It is left to be seen what impact this new threat of the use of nuclear weapons will have on the disarmament question at a global level.
One thing is clear- a declaration of expanding the DPRK's nuclear program 'until the world attains nuclear disarmament' is likely to get many other countries to reconsider their non-nuclear status, especially since experts and researchers do not foresee global disarmament anytime soon.