In November, 1936, Joachim von Ribbentrop negotiated an agreement between Germany and Japan that declared the hostility of the two countries to international communism. In case of an unprovoked attack by the Soviet Union against Germany or Japan, the two nations agreed to consult on what measures to take "to safeguard their common interests". It also agreed that neither nation would make any political treaties with the Soviet Union. Germany also agreed to recognize the Japanese puppet regime in Manchuria. Italy joined the Anti-Comintern Pact in 1937. Adolf Hitler broke the terms of the pact when he signed the Nazi-Soviet Pact in August, 1939.