"When the U.S. declared war on the Axis powers following the devastating attack on Pearl Harbor on 7 December 1941. President Franklin D. Roosevelt asked the Soviet Union to enter the war against Japan. Instead, Stalin and his USSR remained steadfastly neutral. Finally in October 1944, with Hitler's Third Reich doomed to defeat, Stalin acquiesced to American requests and set the price for Soviet involvement in the war against Japan. He stipulated that the Allies must establish a reserve of supplies and equipment in the Soviet Far East and endorse the Soviet Union's territorial claims in East Asia. These included transfer of the Kuril Islands to Soviet control and acknowledging what amounted to U.S. and Soviet spheres of influence in northern China, Manchuria, and Korea. At the February 1945 Yalta Conference, President Roosevelt secured Stalin's promise to enter the war two to three months after the defeat of Germany by accepting these terms."