After repairs were completed, "Littorio" participated in an unsuccessful sortie to intercept British forces on 22–25 August. A month later, she led the attack on the Allied convoy in Operation Halberd on 27 September 1941. The British force escorting the convoy included the battleships , , and ; Italian reconnaissance reported the presence of a powerful escort, and the Italian commander, under orders not to engage unless he possessed a strong numerical superiority, broke off the operation and returned to port. On 13 December, she participated in another sweep to catch a convoy to Malta, but the attempt was broken off after "Vittorio Veneto" was torpedoed by a British submarine. Three days later, she steamed out to escort Operation M42, a supply convoy to Italian and German forces in North Africa. By late 1941, British success at breaking the Enigma code made it increasingly difficult for Axis convoys to reach North Africa. The Italians therefore committed their battle fleet to the convoy effort to better protect the transports. The next day, she took part in the First Battle of Sirte. "Littorio", along with the rest of the distant covering force, engaged the escort of a British convoy heading for Malta that happened to run into the M42 convoy late in the day. "Littorio" opened fire at extreme range, around , but she scored no hits. Nevertheless, the heavy Italian fire forced the British force to withdraw under cover of a smokescreen and the M42 convoy reached North Africa without damage.