A statement from City on Friday confirmed that De Bruyne suffered a lateral collateral ligament (LCL) lesion in his right knee.
De Bruyne only returned to training at City last week, having had a break after helping Belgium finish third in Russian Federation in July.
"Like the doctor said, it will be two to three months, hopefully he can do as much as possible to get back and help us again", Guardiola told a news conference.
"I can only say, when that happens, [of] the last five games four are away, I think, so when you are maybe playing for the Premier League, four games away is a little bit different".
"This can happen because you build an incredible stadium for Tottenham Hotspur - sometimes there are delays, this kind of thing happens".
The Belgium worldwide suffered an injury in training on Wednesday and will be out for three months.
The Premier League champions have strength in depth in midfield but De Bruyne's injury remains a blow.
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However, most of the mid-level phones from Samsung, LG, Sony, Xiaomi, and others will not get the update . Other companies are still at the stage of unveiling lists of phones that will at some point taste Pie.
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The crowd held pictures of the children and chanted slogans against Saudi Arabia and its ally and key arms supplier, the United States.
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The other six will be composed of the four semi finalists of the previous year and two teams invited by the organisation. However, an increasing number of top players have skipped matches in recent years to ease their schedule.
The 27-year-old midfielder - who scored eight goals and provided 16 assists as City romped to the title last season - will not have to undergo surgery on the injury which he suffered in training on Wednesday.
And though Guardiola said there was no way of knowing for sure if the short break led directly to his injury, the manager added that it was hard to guard against any of his other players picking up problems. "More than 11 months and coming back immediately this can happen".
"Nobody knows, but I'm pretty sure this can influence it". If you're fresh, with normal vacations, then that doesn't happen. If you disagree, complain to me for my decisions. We have to play every game like it was an important game. We tried to build something good and you did do good.
City are next in action against Huddersfield at the Etihad this Sunday.
Tottenham have moved their first three fixtures to Wembley, where they played home games last season, but switching the City match to the national stadium is complicated because an NFL game scheduled for the same day.
"He made a decision to rest a little bit more with his wife and his little boy, and play with us". "That is the moment the real man's, the real football players, the real professionals step up and say 'I'm here'".