Bentaleb spent the second half of last season on loan at St James’s Park after a nine-month spell in the cold at the Bundesliga club.
Newcastle, however, didn’t make the move permanent.
Bentaleb, 26, returned to the fold at the Veltins Arena, though he has now been suspended “until further notice”.
Sporting director Jochen Schneider said: “Schalke and Bentaleb clearly aren't a good fit. We will part ways by summer 2021 at the latest."