The Sky Blues offered a quick response to the incident on the club's open-top bus celebrations on Monday, claiming the striker "made a significant error of judgement"
Carlos Tevez insists he will not personally apologise to Sir Alex Ferguson after the striker was pictured with a sign saying "RIP Fergie" during Manchester City's title parade.
The striker was caught with the banner on an open-top bus on Monday, with the message said to be in response to Sir Alex's claim that City would not surpass United in his lifetime.
City offered a prompt apology to the Scot and United, claiming Tevez "made a significant error of judgement".
Tevez issued a general apology for his involvement but has since hit out at his former manager.
"It seems like Ferguson is the President of England," Tevez told reporters at Ezeiza airport as he returned to Buenos Aires.
"Because every time he speaks badly of a player or when he always talked rubbish about me, I never went out to say he had to apologise. When you mess up you should go out and apologise, but I do not apologise.”
The Argentine only recently returned to the first-team squad at City following a six-month exile in his homeland after allegedly refusing to come on as a substitute against Bayern Munich in the Champions League last September.