Barca confirmed the agreement early Sunday morning.
"We don't sign players to smack people around, we do it to improve our team even more. Each year we try to improve the team and we believe that Neymar can help us with our style [of play], even though this year has been fantastic," Rosell told TV3.
Rosell went on to say that there is no date set for the Brazilian's arrival to Barcelona.
He explained: "We have to talk it over with the Brazilian federation. We'll present the player as soon as possible ... The important thing is that we have an agreement."