On September 3, 1940, he succeeded elderly Prince Kan'in Kotohito as Chief of the Imperial Japanese Army General Staff. He was one of the leading Army officers lobbying for war with the West. However, on September 5, 1941, on the verge of the war against the United States and Great Britain, he was severely berated by Emperor Hirohito for having earlier predicted in 1937 that Japanese invasion of China would be completed within three months, and challenged over his confidence in a quick victory over the Western powers.