Two days later, Antonescu forced the king to abdicate and installed the king's young son Michael (Mihai) on the throne, then declared himself "Conducător" ("Leader") with dictatorial powers. The National Legionary State was proclaimed on 14 September, with the Iron Guard ruling together with Antonescu as the sole legal political movement in Romania. Under King Michael I and the military government of Antonescu, Romania signed the Tripartite Pact on November 23, 1940. German troops entered the country on 10 October 1941, officially to train the Romanian Army. Hitler's directive to the troops on 10 October had stated that "it is necessary to avoid even the slightest semblance of military occupation of Romania". The entrance of German troops in Romania determined Italian dictator Benito Mussolini to launch an invasion of Greece, starting the Greco-Italian War. Having secured Hitler's approval in January 1941, Antonescu ousted the Iron Guard from power.