The Juventus and Italy goalkeeper is a big fan of England international Hart but feels he has to win back his place in Manuel Pellegrini's first team at club level in order to be Roy Hodgson's number one at Brazil next year.
"There is usually an order in which you do these things; you normally play for your club and then you play for your national team," the 2006 World Cup winner said.
"To try to play for your national team when you're not playing for your club will become a struggle in the end.
"A player such as Iker Casillas can do it [play for Spain despite being frozen out at Real Madrid] because he has great experience of victory and incredible value as a goalkeeper. But they are very few, those who could succeed in playing for their national team while not playing for their club."
Hart has fallen out of favour at City, in terms of Premier League play, having not appeared since the end of October with Pellegrini preferring Costel Pantilimon in goal. He has played four times in the Champions league but conceded six goals.
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