Conn Iggulden said this quote

Kublai went on as if he had not spoken.“Before you all, in the lands of my enemies, I declare myself great khan of the nation, of the khanates under my brothers, Hulegu and Arik-Boke, of the Chagatai khanate and all others. I declare myself great khan of the Chin lands and the Sung. I have spoken and my word is iron!