Neymar, 21, has been repeatedly linked with Barca and will reportedly hold talks with the club in July.

Discussing his compatriot's chances of establishing himself as a modern great, Ronaldo appears to have suggested Neymar's rumoured switch to Barca is a done deal.

"He has the potential (to become one of the world's best)," the now-retired striker told Tuttosport.

"But we have to assess his impact on European football when he arrives at Barcelona.

"The first year will be difficult for him, but I'm convinced that when he adapts he'll be one of the very best."

Ronaldo enjoyed a fine season at Camp Nou before leaving for Inter Milan in 1997.