The striker recently claimed that he would exit the Spanish club when his contract expires in the summer, but Bilbao have been rumoured to be keen on cashing in on the 27-year-old in the New Year.
"The situation is what it is," Bielsa told reporters. "Llorente leaving in January is something the club have rejected.
"There is already a fixed position, and his presence gives us something extra."
Juventus, Chelsea and Liverpool have all been linked with a move for the forward.