Barcelona president Josep Maria Bartomeu revealed he would first speak to Real Madrid if the LaLiga champions were interested in making a move for out-of-favour midfielder Isco.
Isco has been linked with a move away from the Santiago Bernabeu as he struggles for game time under head coach Santiago Solari.
The 26-year-old, who is contracted until 2022, has only made five league starts for Madrid this season, while coming off the bench 10 times.
He has been a regular in their Copa del Rey campaign, though, meaning he could come up against Barca on Wednesday.
Ahead of the semi-final first leg of the Copa Clasico, Bartomeu discussed how Barca would approach trying to sign the Spain international.
"If our coaches asked us for a player and they want to leave Madrid, of course we would sign them," he told El Partidazo de COPE.
"But it has not happened since I'm here.
"There are no non-aggression pacts. Each one tries to make their team more competitive.
"Isco? For the sake of Real Madrid I would speak with the president of Real Madrid [Florentino Perez]."
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