The 29-year-old was photographed in Turin on Tuesday and the deal is now set to be completed before the 31 August transfer deadline.
Once the deal is confirmed Hart will rejoin the England squad for Sunday’s first 2018 World Cup qualifying match in Slovakia.
Hart is yet to feature in the Premier League under Guardiola, who has signed Chile goalkeeper Claudio Bravo, 33, from Barcelona.
Officials at the club have vowed to help Hart “find the best solution” in order to keep his international place. City are paying some of Hart’s wages to allow him to move to Serie A for the season, though the amount is not known.
Former England full-back Tony Dorigo, who spent a year with Torino between August 1997 and October 1998, believes Hart can be a success at the club.
“It’s a wonderful experience [playing for Torino]. I think Joe needs to get stuck in there with the right attitude, learn the language and just enjoy the experience,” he told BBC Radio 5 live.
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