Video: 'Oval Office Address on the Cuban Missile Crisis - John F. Kennedy - Oct. 22, 1962'

(Monday, October 22, 1962, 7:00 p.m. EDT; day seven of the Cuban missile crisis, part of the Cold War) — U.S. President John F. Kennedy announced tonight in a nationally broadcast address that “unmistakable evidence has established the fact that a series of offensive missile sites” had been established in Cuba by the Soviet Union “to provide a nuclear strike capability against the Western Hemisphere.”

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The missile sites, under construction but nearing completion, were designed to house medium-range missiles capable of striking a number of major cities in the United States, including Washington, D.C.

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Kennedy announced “a strict quarantine on offensive military equipment under shipment to Cuba” and warned that any launch of a nuclear missile from Cuba would require “a full retaliatory response upon the Soviet Union.”

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“I call upon [Soviet leader] Chairman [of the Council of Ministers of the Soviet Union Nikita] Khrushchev to halt and eliminate this clandestine, reckless, and provocative threat to world peace and to stable relations between our nations,” Kennedy implored.

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The quarantine of Cuba began the following day, but Kennedy decided to give Khrushchev more time to consider the U.S. action by pulling the quarantine line back 500 miles.

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By Oct. 24, 1962, Soviet ships en route to Cuba capable of carrying military cargoes appeared to have slowed down, altered, or reversed their course as they approached the quarantine, with the exception of one ship—the tanker Bucharest.

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The crisis would continue for another four days.