The Spain international appears to be on the verge of a much-anticipated €40 million move to Bayern Munich, and, as Goal.com exclusively revealed earlier this week, City failed to convince Daniele De Rossi to leave Roma for the Etihad Stadium and could have considered Javi Martinez as an alternative.
However, it seems City have been put off bidding for the 23-year-old Basque because Mancini believes the Spanish club value their asset too highly.
When asked by reporters on Friday morning if a deal could be done, the coach said it would be "difficult". He added: "The cost is too high for me."
The Italian coach hinted that a potential deal could still by replying “maybe, maybe,” when asked if the former Chelsea youngster would be joining the club this summer.
The Premier League champions have had a quiet transfer window by their usually hectic standards, but the former Inter boss revealed work is going on behind the scenes to bring new faces in with just seven days until deadline day.
"I'm sure we can do what we want in the one week of the [transfer window]," Mancini added. "We are working, working."