Busquets is now free to play Manchester United in the final at Wembley.
"If UEFA has taken that decision it is because it has to be," said Casillas. "Everyone has seen the pictures, know what I mean ...?"
Barca striker David Villa also was part of the media function and said: "It's a very good decision for Barca because he is an important player for us.
"What happens on the field, should stay there."