City academy product Brahim Diaz is reportedly set to join Real after rejecting the opportunity to remain in Manchester.
But Guardiola isn't worried about losing any more of his players to the La Liga giants.
"Barca and Madrid are able to buy these players, but the players are comfortable," said the City manager. "We try to keep these players like every club. We try because they are young - that's why we want to keep them.
"They want to stay - when they want to leave they (can) leave. Kevin, Raheem, Leroy, Gabriel, (John) Stones, they have Europe in front of them, but they like to stay here."