 <unk> negotiations began in <unk> , and ended with <unk> finally agreeing to submit in June <unk> . The <unk> embassy , received by the emperor in Beijing in January <unk> , agreed to a treaty that acknowledged the <unk> of the Yuan dynasty or the <unk> Empire over the Pagan Empire and annual payments in taxes to the <unk> government in exchange for the evacuation of <unk> troops from northern Burma . But the treaty never really took effect as <unk> was assassinated in July <unk> , and no authority who could honor the treaty emerged . The <unk> command at <unk> now deemed the imperial order to withdraw void , and ordered an invasion of central Burma . They may not have reached Pagan , and even if they did , after having suffered heavy casualties , they returned to <unk> . 
