The Seleção will come together ahead of friendlies against Panama and Serbia in Brazil at the beginning of June.
Scolari has already decided how his players will be tested and prepared for the tournament but admitted that he does have concerns about their fitness.
He said: "The players will be evaluated when they present themselves. After we have all the data from the medical and physical [tests] we will define the work. We will work in groups, so that everything is balanced. Only the fitness [of the players] worries me."
