Neymar's future has been a big topic of discussion in the last few weeks, especially after reports claimed the club are willing to listen to offers for his services.
Mbappe, meanwhile, has sorted out his immediate future after signing a new three-year extension while snubbing interest from Spanish giants Real Madrid.
A number of reports claim that Mbappe has been given a say in the club's transfer policy and feels the club would be better without the Neymar due to his "indiscipline".
The Brazilian's off-field issues have been well documented in the last few years during his time in the French capital.
Spanish publication Mundo Deportivo claims that Messi disagrees with the notion that Neymar should leave the Parc des Princes this season.
Messi has built a strong relationship with with Neymar in the last few years and the report adds he feels the Brazilian can still contribute to the side on the field.
Neymar endured a difficult season by his standards after registering 13 goals and eight assists in 28 appearances.