Harry S. Truman announced Japan's unconditional surrender to reporters on August 14, 1945.
Truman made the announcement at the White House after receiving Japan's acceptance of the Allied surrender terms. His statement told the public that Japan had accepted the Potsdam Declaration, which called for the surrender of Japanese armed forces.
The announcement came before Hirohito's radio address to the Japanese people, which was broadcast in Japan on August 15 local time. It also came before the formal signing of the surrender instrument aboard USS Missouri on September 2.
This sequence creates a common date mix-up. In the United States, V-J Day was widely associated with August 14 because Truman's announcement arrived during the evening in Washington. In Japan and several other countries, August 15 is associated with the emperor's broadcast, while September 2 marks the formal signing.