On the Byzantine front, Sulayman took up his predecessor's project to capture Constantinople with increased vigor. His brother Maslama besieged the Byzantine capital from the land, while Umar ibn Hubayra al-Fazari launched a naval campaign against the city. The Byzantines destroyed the Umayyad fleets and defeated Maslama's army, prompting his withdrawal to Syria in 718. The massive losses incurred during the campaign led to a partial retrenchment of Umayyad forces from the captured Byzantine frontier districts, but already in 720, Umayyad raids against Byzantium recommenced. Nevertheless, the goal of conquering Constantinople was effectively abandoned, and the frontier between the two empires stabilized along the line of the Taurus and Anti-Taurus Mountains, over which both sides continued to launch regular raids and counter-raids during the next centuries.