In early 1948, following reports of strengthening "reactionary elements", Soviet operatives executed a coup d'état in Czechoslovakia, the only Eastern Bloc state that the Soviets had permitted to retain democratic structures. The public brutality of the coup shocked Western powers more than any event up to that point, set in motion a brief scare that war would occur, and swept away the last vestiges of opposition to the Marshall Plan in the United States Congress. resulting in the formation of Czechoslovak Socialist Republic. In an immediate aftermath of the crisis, the London Six-Power Conference was held, resulting in the Soviet boycott of the Allied Control Council and its incapacitation, an event marking the beginning of the full-blown Cold War and the end of its prelude, as well as ending any hopes at the time for a single German government and leading to formation in 1949 of the Federal Republic of Germany and German Democratic Republic.