But the new City boss is convinced the England goalkeeper will become a better player if he stays at the Etihad Stadium.
Hart's future has been thrown into doubt after being left on the bench by Guardiola for City's first two games of the season.
There has been speculation linking the 29-year-old with a move away from the club while City have reportedly been targeting other keepers.
Asked if Hart could move if he wishes, Guardiola said: "Of course
I want happiness for the players
I don't want the players to stay here if they don't want to stay.
"All the players here have a contract
If they decide they want to stay they are going to stay, but they know the situation when I spoke with them.
"If they want to leave because they prefer to play every game - not only speaking about Joe, speaking about all the players at the club, the squad - (they can)
I want to live and work with the players who want to stay
That is no doubt."
Guardiola has spoken previously about the importance of a goalkeeper's distribution and footwork to his desired style of play.
The Spaniard currently believes Willy Caballero, having returned for pre-season training before Hart, is more attuned to his ideas.
But Guardiola claims that could change if Hart, who was on the bench for games against Sunderland and Steaua Bucharest, is prepared to stick at it.
He said: "I said to him in the first morning if he stays he is going to improve and he is going to understand what we want from our goalkeeper.
"I met a lot of goalkeepers in the beginning who had problems and after two or three months became one of the best players in that position.
"That can happen, but when we played these two games right now, in that situation he (Caballero) is better, but that does not mean it is going to happen in the future."
Source : PA
Source: PA