Ever since being appointed Foreign Minister in February 1957, Gromyko never challenged the authority of those elected to lead the Soviet Union by the Central Committee. However, this changed when the ailing Konstantin Chernenko rose to become the country's de jure ruler. Unimpressed by the new leader's feeble gasp of foreign relations and weak standing in the Politburo, Gromyko aggressively asserted control over Soviet diplomacy to the point of regularly interrupting and contradicting Chernenko in front of other world leaders. Thus, despite Chernenko's interest in reviving détente, the longtime Foreign Minister's distrust of the West rendered any relaxation of tensions impossible.