The fall of Tunis on 13 May 1943 radically changed the strategic situation. It was important for Germany to control Italy, which had turned into an external stronghold of the Reich, because they were susceptible to invasion. The Germans developed plans for operations "Alarich" and "Konstantin", devoted respectively to the occupation of Italy and to the Balkan areas occupied by the Italian Army, in order to take control of Italy and disarm the Italian forces after their expected armistice with the Allies. In preparation, the Germans wanted to increase land forces in Italy. Ambrosio and Mussolini refused and asked only for more airplanes because they wanted to preserve Italian independence. On 11 June 1943, the Allies captured the island of Pantelleria, the first part of Italy to be lost. Pantelleria had been turned into a citadel by Mussolini, but – unlike Malta – it fell to the Allies without much resistance after a week-long heavy bombardment. It was now apparent that the next Allied move would be the invasion of Sicily, Sardinia, Corsica or Greece.