Van Persie is the subject of a bid from Manchester United.
Van Gaal told a press conference aired on Sky Sports: "I think the player always has to decide for himself.
"When he wants he can ask me for advice but then I'll speak to him, not to you."
He added: "I had the conversation and it was unbelievable. A great and high level, not only at a human side but also in the football vision. It was one of the best meetings I've had with an individual player."