On 12 June, Hitler revealed to Antonescu his plans to invade the Soviet Union. Antonescu promised him full economic and military participation. The population strongly supported the idea, as it was seen as the opportunity to eliminate the Russian threat once and for all. A few hours before the invasion began, Antonescu and Michael I declared a "holy war" for the liberation of Bessarabia and Northern Bukovina. The invasion began on 22 June, but Romanian military operations began on 2 July. After several battles, both regions were reintegrated into the Romanian state on 25 July. A meeting between Hitler and Antonescu on 6 August determined that the area between the Dniester and the Southern Bug rivers (Transnistria) would be placed under Romanian civil administration. Further, Romanian troops would occupy the area between the Southern Bug and Dnieper River and a few others would cross the Dnieper and continue the invasion. On 19 August, the Transnistria Governorate was established, which was not formally annexed to Romania unlike Bessarabia and Northern Bukovina. Many Romanian troops participated in the German offensives in southern Russia and the Caucasus. The defeat at the Battle of Stalingrad convinced Antonescu that a German victory was impossible, and he began to protect the east of Romania, although he continued to support Germany with troops and material.