Officially, the Pact of Steel obliged Germany and Italy to aid the other country militarily, economically or otherwise in the event of war, and to collaborate in wartime production. The Pact aimed to ensure that neither country was able to make peace without the agreement of the other. The agreement was based on the assumption that a war would not occur within three years. When Germany invaded Poland on 1 September 1939 and war broke out on 3 September, Italy was not yet prepared for conflict and had difficulty meeting its obligations. Consequently, Italy did not enter World War II until June 1940, with a delayed invasion of Southern France.