Original: After Lenin's death on 21 January 1924, Rykov gave up his position as Chairman of the USSR Supreme Council of National Economy and became Chairman of the Council of People's Commissars of the USSR and, simultaneously, of the Sovnarkom of the RSFSR, on 2 February 1924.
Simplified: After Lenin's death on 21 January 1924, Rykov became a head of the government of the USSR and Russia.