City turned down a ?40million bid from the Brazilian club last week, with City believed to be holding out for ?50million for a player who finished as joint top scorer in the Premier League last season with 20 goals.
However, speaking on the club's pre-season tour of North America, Mancini told Sky Sports News: "We have an agreement with Corinthians but Carlos now is still a City player."
The Sao Paulo club moved for the Argentina striker after being alerted by Tevez's admission earlier this month that he wished to leave City for the sake of his family, with his two children based in his homeland.
Corinthians president Andres Sanchez last week claimed Juventus had entered the race to sign Tevez but insisted his own club would not increase their offer for the wantaway South American.
Tevez's advisor, Kia Joorabchian, revealed a few days ago that a deal with Corinthians was "close", with the player himself keen on a return to the club he previously represented between January 2005 and August 2006.
The 27-year-old, who joined City from Manchester United in summer 2009 and has also previously played for West Ham, is under contract at City until June 2014.
Asked whether Tevez would now be discussing personal terms, Mancini replied: "I don't know this. I repeat, at the moment, Carlos is still a City player."
He added: "I want to wait. At the moment we are here, we are working with the other guys. We should think about this."
Defender Joleon Lescott admitted he would be disappointed to see his team-mate depart but understood his wishes.
The England international told Sky Sports News: "We'll be disappointed if Carlos leaves but it was down to the club and Carlos what was best for each other and they have come to an agreement so I wish both parties all the best.
"Carlos is his own man. Last season he played to 110% every game so none of us will be holding any grudges towards him and we'll wish him all the best if he does leave."
Source: Team Talk
Source: Team Talk