Malaga vice-president Moayad Shatat insists they'll only sell Isco for the right price.
The midfielder is wanted by Real Madrid and Manchester City.
"He's a magnificent player, very important to us and if the offers do not match what we are looking for then we will not sell the player," Shatat told reporters at the unveiling of new Malaga coach Bernd Schuster.
"We will only sell for the right price, and that price has been set.
"We have no need to sell if the price is not right."