The 34-year-old midfielder has yet to feature this season and was surprisingly left back at home for Wednesday's comfortable 4-0 Champions League victory over Feyenoord.
Guardiola banished the giant Ivorian during the first-half of the last campaign because he felt the 34-year-old was carrying too much weight, putting his former Barcelona charge on notice.
And the City boss stated before the trip to Rotterdam this week: "I spoke with him (Toure) and he knows the reason why - but it's between him and me.
"It's a sporting decision. I'm always happy - but of course I demand as much as possible. I want more, not just from Yaya - I want more from everyone."
Toure's outspoken Russian representative, Seluk, who is disliked by Guardiola, has tweeted: "Yaya is in great shape.
"He will prove it. He is fit to play. It's up to Guardiola to decide."
Toure appeared to be back in Guardiola's good books after getting himself fit and was handed a 12-month deal at the end of last term, although the City boss is a strict disciplinarian when it comes to his players maintaining an ideal body weight, and club insiders have noted the four-time African Footballer of the Year does appear to have returned bulkier.