The Arsenal forward seems unlikely to sign an extension with the Gunners, and City has become the most likely destination.
Guardiola explained: "We have two really good strikers with Sergio and Gabriel. In that position we are good.
"The problem we had last season was Gabriel was out for a long time and I would like to have both Sergio and Gabriel play more games together.
"Last season, we had a lack of goals despite creating a lot of chances. It was a little bit of a problem.
"Of course the responsibility to score goals is not just on Sergio and Gabriel. It is also on the wingers.
"But Sane had a very good six months in the second half of the season. He was outstanding and made a huge step forward. In the beginning he was a bit shy but he showed his quality."
"Alexis is a player from Arsenal. If Arsene said that it is because he knows more than me," Guardiola said.