Jia Sidao
In 1258, Möngke put Kublai in command of the Eastern Army and summoned him to assist with an attack on Sichuan. As he was suffering from gout, Kublai was allowed to stay home, but he moved to assist Möngke anyway. Before Kublai arrived in 1259, word reached him that Möngke had died. Kublai decided to keep the death of his brother secret and continued the attack on Wuhan, near the Yangtze. While Kublai's force besieged Wuchang, Uryankhadai joined him. The Song minister Jia Sidao secretly approached Kublai to propose terms. He offered an annual tribute of 200,000 taels of silver and 200,000 bolts of silk, in exchange for Mongol agreement to the Yangtze as the frontier between the states. Kublai declined at first but later reached a peace agreement with Jia Sidao.