Perez said that bringing in Carlo Ancelotti as coach was the first step and that now Real will continue to look to bring in players of the calibre of Isco.
"Ancelotti was the first step, and now little by little we are strengthening our team, because as our coach says, we have to be able to offer a spectacular kind of football," Marca quotes Perez as saying.
"We want players of a very high level who are hungry and dream of winning over our fans. For that reason we today present Isco to the supporters. Isco, you have come to a club where we do not accept that the word 'impossible' exists.
"Today, the difficult task of getting what is best for Real Madrid with both national and international players is made a reality by your signing for this club."
Isco has been capped at every youth level for Spain and has one full international appearance.