"I don't think Sergio will be out for long and we are hoping he will be back after the international break which is obviously fantastic news for him and for us," manager Roberto Mancini told the club's website on Wednesday.
There are 2014 World Cup qualifiers scheduled for September 7 and 11. It is hoped the Argentine striker could return to action for City against Stoke City in the league on September 15.
"We were very worried a couple of days ago because we feared he could be out for six months or maybe even more which would have been very bad news," added Mancini.
"It looked like a strange injury at the time and because it was his knee we were obviously very concerned so this news is a relief."
Aguero was carried off on a stretcher early in the first half of City's 3-2 comeback win against promoted Southampton and appeared in severe pain, although on Tuesday the 24-year-old calmed fears by saying on Twitter it was not a serious injury.
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