Meanwhile, during the campaign against Zhu and Wang, Wang had put Niu Yuanyi (), a general loyal to the imperial government, under siege at Shen Prefecture (深州, in modern Hengshui, Hebei). Yu Fang (), an advisor to an imperial prince, who wanted to submit an extraordinary suggestion to gain a promotion, suggested to Yuan that Yu's friends Wang Zhao () and Yu Youming () be sent to Wang Tingcou's Chengde Circuit (成德, headquartered in modern Shijiazhuang, Hebei) to try to persuade Wang Tingcou's officers to lift the siege on Shen Prefecture. Yuan accepted the idea, and, as part of the plan, gave Wang Zhao and Yuan Youming some 20 commission certificates to give them to Wang Tingcou's officers. A man named Li Shang () heard of the plan, but misinterpreted this as a plot by Yuan and Yu Fang to assassinate Pei. He reported this to Pei, but Pei took no action. He then reported it to the Left Shence Army (). After Emperor Muzong received report of this, he had Han Gao investigate the matter. After the investigation was complete, it was concluded that there was no evidence that Yuan intended to assassinate Pei, but as a result, both Pei (who by this point had returned to Chang'an and was again serving as chancellor) and Yuan were relieved of their chancellor posts, less than four months after Yuan was made chancellor. Yuan was sent out of the capital to serve as the prefect of Tong Prefecture (同州, in modern Weinan). When a number of advisorial officials subsequently submitted objections that Yuan's punishment was too light, Emperor Muzong stripped Yuan of one of his ceremonial posts as the director of Changchun Palace (長春宮, in Tong Prefecture). While the investigations were still ongoing, the mayor of Jingzhao Municipality (京兆, i.e., the Chang'an region), Liu Zungu (), was putting Yuan's house under constant guard. When Yuan complained about this, Emperor Muzong punished Liu.