Guardiola won 20 trophies during a glittering 10 years at the helm before departing in May.
"I want every single @ManCity fan to know I am here; more than ever," the former Barcelona and Bayern Munich coach posted on X.
"I am, always have been, always will, be behind my club, my owner, my chairman, (CEO) Ferran (Soriano), the players, staff, Enzo (Maresca) and you, our unique supporters.
"Let me be clear: we will get through this together. I love you all."
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