The big spenders have submitted a ?40m bid for the striker, who is Diego Maradona's son-in-law. But City need to come up with another ?5m to invoke his release clause from Atletico Madrid.
Aguero, 23, is keen to move to City and is prepared to leave his new ?5m home in Madrid. Aguero's agent Jose Segui is due in Manchester in the next 48 hours to persuade City to offer the additional funds.
Wanted man: Sergio Aguero (centre) could be set to complete a ?45m transfer to Manchester City
A proposed move to Juventus broke down last month because the former European champions refused to up their ?40m offer, while Atletico will not budge on their valuation and the terms of his release clause.
Segui will also tell the FA Cup winners his client wants ?7m a year - well within their budget.
City boss Roberto Mancini has identified the Argentina striker as the successor to Carlos Tevez. And a deal for Aguero would pave the way for the City skipper's exit.
Tevez, the club's top scorer last season, has told City he wants to leave.
I want to break free! Tevez has repeatedly stated his desire to leave
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Source: Daily Mail
Source: Daily Mail