which they never fully recovered and became a turning point in the war. After Stalingrad, Soviet forces drove through Eastern Europe to Berlin before Germany surrendered in 1945. The German Army suffered 80% of its military deaths in the Eastern Front. Harry Hopkins, a close foreign policy advisor to Franklin D. Roosevelt, spoke on 10 August 1943 of the USSR's decisive role in the war. In the same year, the USSR, in fulfilment of its agreement with the Allies at the Yalta Conference, denounced the Soviet–Japanese Neutrality Pact in April 1945 and invaded Manchukuo and other Japan-controlled territories on 9 August 1945. This conflict ended with a decisive Soviet victory, contributing to the unconditional surrender of Japan and the end of World War II. The USSR suffered greatly in the war, losing around 27 million people. Approximately 2.8 million Soviet POWs died of starvation, mistreatment, or executions in just eight months of 1941–42. During the war, the country together with the United States, the United Kingdom and China were considered the Big Four Allied powers, and later became the Four Policemen that formed the basis of the United Nations Security Council. It emerged as a superpower in the post-war period. Once denied diplomatic recognition by the Western world, the USSR had official relations with practically every country by the late 1940s. A member of the United Nations at its foundation in 1945, the country became one of the five permanent members of the United Nations Security Council, which gave it the right to veto any of its resolutions. Cold War During the immediate post-war period, the Soviet Union rebuilt and expanded its economy, while maintaining its strictly centralized control. It took effective control over most of the countries of Eastern Europe (except Yugoslavia and later Albania), turning them into satellite states. The USSR bound its satellite states in a military alliance, the Warsaw Pact, in 1955, and an economic organization, Council for Mutual Economic Assistance or Comecon, a counterpart to the European Economic Community (EEC), from 1949 to 1991. The USSR concentrated on its own recovery, seizing and transferring most of Germany's industrial plants, and it exacted war reparations from East Germany, Hungary, Romania, and Bulgaria using Soviet-dominated joint enterprises. It also instituted trading arrangements deliberately designed to favour the country. Moscow controlled the Communist parties that ruled the satellite states, and they followed orders from the Kremlin. Later, the