At the end of 1281, Alfonso sent Sancho to Granada for further negotiations and Muhammad agreed to renew his vassalage to Castile. However, Alfonso accused Sancho of acting treacherously and of appropriating Muhammad's tribute. A rift broke out between the king and his son, which weakened the Castilian threat to Granada. Alfonso ended up asking for Abu Yusuf's help against Sancho, and the two monarchs campaigned together against Sancho's partisans in Castile. Meanwhile, Muhammad sealed an alliance with Sancho at Priego in late 1282. At the end of 1283, Abu Yusuf attacked Málaga, forcing Muhammad to sue for peace. Mediated by Abu Yusuf's son, Abu Yaqub Yusuf, they agreed to reconcile and attack the Christians together.