In order to force the Bulgarians, a relative of John V, Count Amadeus VI of Savoy, then leading his own the Savoyard crusade, attacked the Bulgarian coastal towns. In the fall of the same year Amadeo's navy captured Anchialos, Mesembria, Emona and on 25 October he besieged the strong fortress Varna, where he was repulsed. As a result, Ivan Alexander gave the Byzantines safe conduct across Bulgaria and they kept the conquered towns.
In an effort to compel the Bulgarians, a descendant of John V, Count Amadeus VI of Savoy, who was leading his own campaign in the Savoyard crusade, launched an assault on the Bulgarian coastal cities. In the same year, Amadeo's naval forces captured Anchialos, Mesembria, Emona, and on October 25, he laid siege to the fortified city of Varna, where he was ultimately repelled. As a consequence, Ivan Alexander granted the Byzantines safe passage through Bulgaria, allowing them to maintain control over the conquered territories.