Budapest Memorandum

The 1994 diplomatic agreement in which Russia, the United Kingdom, and the United States gave security assurances to Ukraine in connection with its accession to the Nuclear Non-Proliferation Treaty.

Security assurance: A political commitment to respect or support another state's security without necessarily promising military intervention. The memorandum's commitments are assurances, not an explicit guarantee to defend Ukraine with armed force.
Dissolution of the Soviet Union: The 1991 breakup of the Soviet Union into fifteen independent states. Independence left Ukraine with nuclear weapons on its territory and a new security policy to negotiate.
Annexation of Crimea by the Russian Federation: Russia's 2014 seizure and subsequent incorporation of Crimea, a territory internationally recognized as part of Ukraine. The annexation brought the memorandum's assurances into sharp focus.
North Atlantic Treaty: The 1949 treaty establishing NATO and requiring each member to assist an ally under armed attack, through actions each deems necessary. Unlike NATO's Article 5, the memorandum contains no mutual-defense obligation.
Nuclear Non-Proliferation Treaty: A 1968 treaty that seeks to prevent the spread of nuclear weapons while supporting peaceful nuclear cooperation and disarmament. Ukraine joined the treaty as a non-nuclear-weapon state in the context of the memorandum.
Leonid Kuchma: Ukrainian politician who served as the country's second president from 1994 to 2005. Kuchma represented Ukraine at the memorandum's signing as president.
Russian invasion of Ukraine: Russia's full-scale invasion of Ukraine, launched on 24 February 2022, following its 2014 military intervention. The invasion intensified scrutiny of Russia's commitments and the other signatories' responses.
NATO Article 5: The North Atlantic Treaty provision treating an armed attack on one NATO member as an attack on all, while leaving each member to choose its response. Its collective-defense language provides a clear contrast with the memorandum's security assurances.
Treaty: A written agreement between states governed by international law. The memorandum's status and enforceability are often contrasted with those of a ratified treaty.
Bill Clinton: American politician who served as president of the United States from 1993 to 2001. Clinton signed the memorandum for the United States.

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