 During the power struggles which followed Lenin 's death in 1924 , Molotov remained a loyal supporter of Stalin against his various rivals : first Leon Trotsky , later Lev Kamenev and Grigory Zinoviev and finally Nikolai Bukharin . Molotov became a leading figure in the " Stalinist centre " of the party , which also included Kliment Voroshilov and Sergo Ordzhonikidze . Trotsky and his supporters underestimated Molotov , as did many others . Trotsky called him " mediocrity personified " , whilst Molotov himself pedantically corrected comrades referring to him as ' Stone Arse ' by saying that Lenin had actually dubbed him ' Iron Arse ' . However , this outward dullness concealed a sharp mind and great administrative talent . He operated mainly behind the scenes and cultivated an image of a colourless bureaucrat – for example , he was the only Bolshevik leader who always wore a suit and tie . In 1928 Molotov replaced Nikolai <unk> as First Secretary of the Moscow Communist Party and held that position until 15 August 1929 . In a lengthy address to the Central Committee in 1929 , Molotov told the members that the Soviet government would initiate a compulsory collectivisation campaign to solve the agrarian backwardness of Soviet agriculture . 
