Victor Emmanuel III
"Victor Emmanuel III (11 November 1869 – 28 December 1947), born Vittorio Emanuele Ferdinando Maria Gennaro di Savoia, was King of Italy from 29 July 1900 until his abdication on 9 May 1946. A member of the House of Savoy, he also reigned as Emperor of Ethiopia (1936–41) and King of the Albanians (1939–43) following the Italian invasions of Ethiopia and Albania. During his reign of nearly 46 years, which began after the assassination of his father Umberto I, the Kingdom of Italy became involved in two world wars. His reign also encompassed the birth, rise, and fall of the Fascist regime in Italy."1
"During the early 1920s, several short-serving prime ministers, including the well-respected Giolitti, serving an unprecedented fifth term as prime minister, could not unify the country in the face of the growing Italian fascist movement. Strengthened by the economic downturn facing the country, the National Fascist Party led the March on Rome, and he appointed Benito Mussolini as prime minister. Victor Emmanuel remained silent on the domestic political abuses of Fascist Italy, and he accepted the additional crowns of the Emperor of Ethiopia in 1936 and the King of Albania in 1939 as a result of Italian imperialism under fascism. When World War II broke out in 1939, Victor Emmanuel advised Mussolini against entering the war. In June 1940, he relented and granted Mussolini sweeping powers to enter and conduct the war."1
Notice that it was Victor who granted Mussolini his powers. And later...
"Amidst the Allied invasion of Italy in 1943, Victor Emmanuel deposed Mussolini and signed the armistice of Cassibile with the Allies in September 1943."1 So it was within Victor's power all along to remove Mussolini had he the will to do so.