Coulibaly is highly regarded in France and is rated as one of the best prospects in his homeland after coming through the ranks at Rennes.
The powerful central defender has represented France at all age levels from U16 to U18s and he has caught the eye for his country.
Coulibaly was a regular in Rennes' reserve team last season and he is expected to break into the first team next season.
The likes of Newcastle and Liverpool are thought to have watched Coulibaly and they are keeping tabs on his progress as they weigh up moves to bring him to England.
Fiorentina and Sevilla are also chasing Coulibaly and, although Rennes are determined to keep the teenager, they are bracing themselves for offers for the defender.