That’s the view of PSG manager Thomas Tuchel, who wants both players to stay but is unsure if they will.
Neymar joined PSG in 2017 for a world-record £240m deal while Mbappe joined for £180m.
Both have been brilliant for the Parisian club but there’s a feeling among most fans that both could be plying their trade in a more competitive league.
The only achievement for then left to complete in Paris is to win the Champions League but they have failed to do so despite spending huge amounts of money.
And Tuchel, whose future at PSG is also uncertain, has said he wants both stars to stay in Paris.
But he also notes it would be naive to promise that neither of them would be tempted to move on.
“My wish as a manager and as a coach is clear,” he told Sky Sports News.
“I want all my players to stay at PSG and stay with our project. The work is not finished, it has just started.
“My wish is clear, but I can’t promise as that would be naïve and I don’t want to be naïve in this business”
Mbappe sparked transfer speculation last month by saying that he was at a turning point in his career.
The World Cup winner was Ligue 1’s too scorer last season with 30 goals.
“I want to thank all of the people who put together this league. I succeeded in adapting in my first year, to change position this year,” he said.
“There were some disappointments, but that is part of football. This is a very important moment for me.
“I am arriving at the second turning point in my career. I have discovered an enormous amount of things here.
“It is maybe the moment to have more responsibilities, maybe at PSG, with pleasure, or elsewhere for a new project. In any case thanks everyone!”