Treaty on the Non-Proliferation of Nuclear Weapons (NPT) 

The Treaty on the Non-Proliferation of Nuclear Weapons, also called the Non-Proliferation Treaty (NPT), obligates the five acknowledged nuclear-weapon states, the United States, Russian Federation, United Kingdom, France, and China, not to transfer nuclear weapons, other nuclear explosive devices, or their technology to any non-nuclear-weapon state. Nuclear weapon States Parties are also obligated, under Article VI, to "pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race..." Nuclear weapons states must make available to the non-weapons states nuclear technology for peaceful purposes. While non-nuclear-weapon States Parties promise not to acquire or produce nuclear weapons or nuclear explosive devices and to accept safeguards to detect diversions of nuclear materials from peaceful activities, such as power generation, to the production of nuclear weapons. Each non-nuclear-weapon State Party must develop a safeguards agreement with the International Atomic Energy Agency (IAEA). Under these agreements, all nuclear materials in peaceful civil facilities under the jurisdiction of the state must be declared to the IAEA, whose inspectors have routine access to the facilities for periodic monitoring and inspections. If information from routine inspections is not sufficient to fulfill its responsibilities, the IAEA may consult with the state regarding special inspections within or outside declared facilities.

The NPT was opened for signature on 01 July 1968, and signed on that date by the United States, the United Kingdom, the Soviet Union, and 59 other countries. The Treaty entered into force with the deposit of US ratification on 05 March 1970. China acceded to the NPT as a NWS on 09 March 1992, and France acceded as a NWS on 03 August 1992. In 1996, Belarus joined Ukraine and Kazakhstan in removing and transferring to the Russian Federation the last of the remaining former Soviet nuclear weapons located within their territories, and each of these nations has become a NNWS. In June 1997 Brazil acceded to the NPT as a NNWS.

The NPT is the most widely accepted arms control agreement; only Israel, India, and Pakistan have never been signatories of the Treaty, and North Korea withdrew from the Treaty in 2003.

In 1995 the NPT was indefinitely extended at that year's Review and Extension Conference.