In 1960, KB-11 (now VNIIEF) began developing a thermonuclear device with a design capacity of one hundred megatons. In February 1961, the leaders of KB-11 sent a letter to the Central Committee of the CPSU with the subject line "Some questions of the development of nuclear weapons and methods of their use," which, among other things, raised the question of the expediency of developing such a 100 Mt device. On July 10, 1961, a discussion took place in the Central Committee of the CPSU, at which Nikita Khrushchev supported the development and testing of this super-powerful bomb.