In January 1943, British Prime Minister Winston Churchill, American President Franklin D. Roosevelt, and their staffs reorganised the Allied air forces in the North African and Mediterranean Theater of Operations (MTO) at the Casablanca Conference. The Western Desert Air Force became a sub-command of Coningham's Northwest African Tactical Air Force (part of Northwest African Air Forces) in February 1943 and Air Vice Marshal Harry Broadhurst became its Air Officer Commanding. On 18 February 1943, the Mediterranean Air Command (MAC) was established with Air Chief Marshal Sir Arthur Tedder in charge of all Allied air forces in the Mediterranean Theater of Operations (MTO).