The Ghana international is on loan at Massimiliano Allegri's men from their bitter Giuseppe Meazza rivals, and has featured regularly in the Rossoneri's starting XI.
With Milan one point behind Juventus in the race for the Scudetto with two games remaining, the African midfielder has his fingers crossed for victory this weekend.
"Sunday’s match is very important and we have to win it to keep our Scudetto hopes alive," Muntari told Rai Sport.
"I am very happy at Milan now. I came here with great enthusiasm. At Inter, however, I didn’t play consistently and could not be happy.
"I score more now because playing with great talents who help you, like Zlatan Ibrahimovic, Antonio Cassano and Kevin-Prince Boateng, certainly puts you in a good position to give your best.
"I won’t think about my future now, as I am concentrated on the next two games. At the end of the season we’ll talk it over with the club."
Sunday's Derby della Madonnina kicks-off at 20.45 CET.
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