The Argentina striker has been linked with Barcelona and Manchester United this summer.
But agent Fernando Hidalgo told Solo para culés: "I understand that many calls came to them, but always, from what I have talked to the managers, is that Atlético's position in this market is that Julián stays for the next season.
"Julián's admiration for Spanish clubs is already known. And obviously by following Leo Messi's career as a boy ... I do not think there are many Argentines who do not have a feeling towards Barça.
"More this season also how Barça played, Julián is very grateful to many players who have always spoken highly of Julián, like (Pau) Cubarsí. That makes him motivated, but I repeat that today is Atlético, he is very happy here.
"We will see what the negotiation is like. You know perfectly well that football is very changing and good things are going to come."