During the 20th Congress of the Communist Party of the Soviet Union Khrushchev criticised Stalin's rule and his "cult of personality". He accused Stalin of reducing the Party's activities and putting an end to Party democracy among others. In the three years following Stalin's death, the Central Committee and the Presidium (Politburo) worked consistently to uphold the collective leadership lost under Stalin. Khrushchev's rule as First Secretary remained highly controversial throughout his rule in the Party leadership. The first attempt to depose Khrushchev came in 1957, when the so-called Anti-Party Group accused him of individualistic leadership. The coup failed, but Khrushchev's position weakened drastically. However, Khrushchev continued to portray his regime as a "rule of the collective" even after becoming Chairman of the Council of Ministers (Premier), replacing Nikolai Bulganin.