The Uruguay international has been strongly linked with a move to Chelsea in recent months.
“I have offered a guarantee to the coach that no important players will leave the team in January, and that includes Alvaro Pereira,” Da Costa told O Jogo.
“I think the chance to do a deal for this player has passed, and that is good news for us.
“Now is the time that rumours start spreading in the papers, but I am used to that.”
