The Treaty on the Non-Proliferation of Nuclear Weapons is an agreement signed in 1968, to limit the nuclear armament of five countries, the United States, Russia, the United Kingdom, France and China, which were obliged not to transfer arms to the so-called “non-nuclear countries”, nor assist them in obtaining them. China and France only ratified the treaty in 1992. The treaty entered into force on 5 March 1970.
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