李德裕
By summer 842, Wujie Khan was openly attacking Tang border regions. Emperor Wuzong put Li Deyu in charge of drafting various rebukes against Wujie Khan and his advisors, urging them to reconsider their attacks. Also, with Wujie Khan forcing Princess Taihe to submit requests to allow Huigu to borrow Tiande as an operation base, Emperor Wuzong had Li Deyu write her a response back, stating: