Schalke are ready to sign permanently Manchester City defender Matija Nastasic.

Nastasic has not missed a game since joining Schalke in January.

Schalke chief Horst Heldt said: "There is an option to buy Matija Nastasic, that comes into force after a certain amount of minutes he's played and Nastasic's first weeks in general.

"I always confirmed, and I do so now, that we have an option to buy, but this option is conditioned on several situations which must arise. That is a good paraphrase.

"I can confirm that it is connected to situations which must arise. I don't want to narrow it down that it is just connected on appearances, but they are a subject."