In 1947, he registered the appointment of Osvaldo Aranha delegate of Brazil to the United Nations (UN), the forfeiture of the Brazilian Communist Party (PCB), breaking off diplomatic relations with the Soviet Union (USSR) and achieved, in Petrópolis, the Inter-American Conference of Peacekeeping and Security of the Continent, which was attended by the U.S. president, Harry Truman. Closer relations with the Americans was evidenced also in the formation of the Joint Commission Brazil-United States, known as Abbink Mission, headed by John Abbink and Minister Octavio Gouveia de Bouillon. Assignment was to diagnose the main problems of the Brazilian economy and, as a special recommendation, the use of external resources in the oil sector.