The former EAC secretary-general replaces Louise Mushikiwabo.
The former East African Community secretary-general Richard Sezibera has been appointed by President Paul Kagame as Rwanda's new Foreign Affairs minister.
Dr Sezibera, 54, prior to heading the EAC Secretariat was the Minister of Health and also served as the presidential advisor on security in the Great Lakes Region.
After completing his five-year term at the EAC in Arusha, Tanzania, he returned to Rwanda and vied in a senatorial by-election in 2016, which he won becoming the Southern Province senator.
He replaces Ms Louise Mushikiwabo who was recently elected as the secretary-general of the International Organisation of the Francophonie (OIF), the French-speaking countries bloc.
Ms Mushikiwabo served as Minister of Foreign Affairs since 2009.