The relationship between Zhukov and Khrushchev reached its peak during the 20th Congress of the Communist Party of the Soviet Union in 1956. After becoming the First Secretary of the Party, Khrushchev moved against Stalin's legacy and criticised his personality cult in a speech, "On the Cult of Personality and Its Consequences." To complete such startling acts, Khrushchev needed the approval—or at least the acquiescence—of the military, headed by Minister of Defense Zhukov.