Mancini says it is now time the moody striker knuckled down to help Manchester City.
The Etihad boss said: "Mario stays here.
"We didn't have any requests about Mario and he has another three years on his contract.
"Mario should work well and try to get his place in the team because at the moment he doesn't play - for many reasons.
"At the moment his performance is so-so. But he can improve because in next four months we have important and crucial games in Premier League and FA Cup."