 In January <unk> , the embassy arrived at Beijing , and was received by the Yuan emperor . The <unk> delegation formally acknowledged <unk> <unk> of their kingdom , and agreed to pay annual tribute tied to the agricultural output of the country . ( Indeed , the tribute was no longer nominal . ) In exchange , the emperor agreed to withdraw his troops . For the emperor , the Burma campaign was the only bright spot ; his other Southeast Asian expeditions had gone badly . He did not want to invest more troops <unk> the rest of the kingdom . He preferred a vassal ruler . The <unk> embassy arrived back at <unk> in May <unk> , and reported the terms to the king . 
