When Emperor Mingzong sent an emissary to question Gao about what happened to Han, Gao responded: "Han Gong and the others took ships down the Gorges and had to go thousands of li. If you want to know why their ships overturned and they drowned, you should question the river god." In anger, Emperor Mingzong stripped Gao of his titles and commissioned Liu Xun () the military governor of Shannan East to attack Gao from the north, with Xia Luqi () the military governor of Zhongwu Circuit (忠武, headquartered in modern Xuchang) as Liu's deputy; Dong Zhang the military governor of Dongchuan Circuit (東川, headquartered in modern Mianyang, Sichuan) to attack him from the west, with Xifang as Dong's deputy; and Ma Yin to attack from the south. Liu quickly put Jiangling under siege, but as Jiangling was humid, and it happened to be rainy season, the siege was hampered, with many of Liu's soldiers and Liu himself becoming ill. Emperor Mingzong sent Kong Xun, who had become his chief of staff, to Jiangling to oversee the siege. Kong, who was also unable to capture Jiangling, sent emissaries into the city to try to persuade Gao to submit. Gao not only refused to do so, but was rude to Kong's emissaries. Meanwhile, despite Emperor Mingzong's sending much gifts to Ma, Ma found excuses not to attack Jiangling. With the siege unsuccessful, Emperor Mingzong ordered Liu to withdraw. However, Xifang was able to defeat Jingnan forces stationed at Kui, Zhong, and Wan, and recapture those three prefectures for the Later Tang imperial government. Emperor Mingzong created a Ningjiang Circuit (), with its headquarters at Kui, and made Xifang its military governor. Despite Xifang's victory, Emperor Mingzong blamed the approval of Gao's petition to take the three prefectures on the former chancellors Doulu Ge and Wei Yue, and ordered them to commit suicide. Around the same time, Gao intercepted and captured Ma's tributary emissary to Emperor Mingzong, Shi Guangxian (), as well as the awards that Emperor Mingzong was sending Ma via Shi. He thereafter submitted a petition requesting to be a Wu vassal. However, the Wu regent Xu Wen believed that it would be ill-advised for Wu to accept Gao as a vassal, pointing out that Jiangling was much closer to the Later Tang capital Luoyang than to Wu's capital Guangling (廣陵, in modern Yangzhou, Jiangsu) and therefore it would be