The Citizens manager has mounting selection problems, with Maicon, Michah Richards, Jack Rodwell and Aleksandar Kolarov all sidelined with injuries.
In addition, Kolo Touré and Yaya Touré are set to feature for the Ivory Coast at the Africa Cup of Nations, while Samir Nasri is banned for three games following his sending off at Norwich.
Mario Balotelli has been linked with a return to Italy in recent weeks amid interest from AC Milan, but Mancini insisted that no players will be leaving the Etihad Stadium next month.
“We can’t sell players,” said Mancini.
“We don’t have enough players to play if we sell players. We can have a problem because we lose three [Ivory Coast] players.
“I don’t think Micah will play until end of February. We don’t know when Jack can play. Maybe we can recover Kolarov in two weeks.
“Maicon went to Italy for treatment on his knee and he comes back tomorrow [Tuesday].”
Balotelli has not featured for City since their 3-2 loss to Manchester United but Mancini said that the Italian striker could recover from a virus in time for their FA Cup clash against Bradford City.
“Mario is getting better,” Mancini added. “He trained yesterday [Sunday]. He could be ready for Watford.”
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