With the end of the war drawing near, Truman flew to Berlin for the Potsdam Conference, to meet with Soviet leader Joseph Stalin and British leader Winston Churchill regarding the post-war order. Several major decisions were made at the Potsdam Conference: Germany would be divided into four occupation zones (among the three powers and France), Germany's border was to be shifted west to the Oder–Neisse line, a Soviet-backed group was recognized as the legitimate government of Poland, and Vietnam was to be partitioned at the 16th parallel. The Soviet Union also agreed to launch an invasion of Japanese-held Manchuria. While at the Potsdam Conference, Truman was informed that the Trinity test of the first atomic bomb on July 16 had been successful. He hinted to Stalin that the U.S. was about to use a new kind of weapon against the Japanese. Though this was the first time the Soviets had been officially given information about the atomic bomb, Stalin was already aware of the bomb project, having learned about it through espionage long before Truman did.