The top flight duo had both been linked with the highly-rated centre-back this summer, who reportedly has a €45m release clause in his Porto contract.
And it looks like he'll be staying put, after Ferrari claimed Mangala is resolved to playing another season for the reigning Portuguese champions.
"Yes, he will stay at FC Porto," Ferrari is quoted as saying by A Bola.
"There is no possibility of him leaving. It is the end of the season."
The France international is under contract until 2016, but Ferrari seems to suggest Mangala could be open to a switch at the end of this season.
Manchester United, as well as Chelsea and City, have scouted the 22-year-old within the past 12 months and have been impressed by what they've seen.
Mangala joined Porto from Standard Liege in 2011, and quickly became one of the most consistent performers in Liga Sagres.
Chelsea had reportedly identified him as the perfect partner for David Luiz, while City were thought to be on the lookout to strengthen their defensive options.
Ultimately Manuel Pellegrini opted for the cheaper option, agreeing a deal for 32-year-old Atletico Madrid centre-back Martín Demichelis.