The Ubangi River ( or ), also spelled Oubangui, is the largest right-bank tributary of the Congo River in the region of Central Africa. It begins at the confluence of the Mbomou and Uele Rivers and flows west, forming the border between Central African Republic and Democratic Republic of the Congo. Subsequently Ubangi bends to the southwest and passes through Bangui, the capital of CAF, after which it flows south - forming the border between Democratic Republic of the Congo and Republic of Congo. Ubangi finally joins the Congo river at Liranga.