In 1934, Hitler told his military leaders that a war in the east should begin in 1942.[59] The Saarland, which had been placed under League of Nations supervision for 15 years at the end of World War I, voted in January 1935 to become part of Germany.[60] In March 1935, Hitler announced the creation of an air force, and that the Reichswehr would be increased to 550,000 men.[61] Britain agreed to Germany building a naval fleet with the signing of the Anglo-German Naval Agreement on 18 June 1935.[62]