Tevez missed his third game in a row after returning to his native Argentina last week when his wife gave birth prematurely.
The 19-goal striker was conspicuous by his absence as City and their fellow Champions League hopefuls played out a dour and disjointed goalless draw at Eastlands.
- Man City 1-1 Liverpool
The eagerly awaited clash between the fourth and fifth-placed teams proved a disappointing affair as neither looked like a side ready to compete amongst Europe's elite.
City take on Stoke City in an FA Cup fifth-round replay on Wednesday before a Premier League trip to Chelsea on Saturday and Mancini has urged Tevez to return to England ahead of a make-or-break period of the season.
"I don't know where Tevez is - I think in Argentina," he explained. "It's a big problem for us because we have an important week and we don't have Tevez. For me it is no good.
"Carlos has been eight days at home and I don't know if while in Argentina he has been working.
"I hope Carlos, within the next two days, can come back here because we need him. Maybe he is on the plane.
"I spoke to him three days ago. He had some problems with his family but now it has been resolved and I hope he comes back.
"I think he will come back in two days. I need him."
Speaking about the disappointing stalemate which left City down in fifth place in the Premier League table, Mancini added: "At the end of the game the draw was the right result as we didn't concede any chances to Liverpool and they did not concede any chances to us.
"We played against a top squad and we played very well, as a team, which is important."
Source: DSG
