The Italian worked with Milan's Swedish striker during a successful spell at Inter but insists his forward line does not need strengthening this summer
The Italian led his side to a maiden Premier League title this term with a last-gasp victory over QPR on the final day of the season.
And City have since been strongly linked with a move for the Sweden international as they look to retain their crown next term.
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However, the 47-year-old boss insists a forward line of Carlos Tevez, Sergio Aguero, Edin Dzeko and Mario Balotelli is strong enough.
"Ibrahimovic is a champion," Mancini told Gazzetta dello Sport.
"But I already have four very strong strikers. I just need them to compete in the Champions League. We are okay up front."
The 30-year-old striker scored 35 goals in 44 appearances for the Milan outfit last term, as they finished second in Serie A and reached the last eight of the Champions League.
He is set to captain Sweden at Euro 2012 this summer, who have been drawn in Group D alongside France, Ukraine and England.