Both clubs have been linked with returns to England after Leicester and Everton opted to part ways with their managers, while West Ham are also said to be on the verge of parting ways with Slaven Bilic.
While addressing whether Ancelotti could return to management soon, Vialli said: "I doubt it. I think for this season he might want to take a little break and rest a little bit and think about his next move very carefully.
"But I don't think he's desperate to get a job. So, I don't think he will say yes to any of these offers –if they came up."
About Mancini, he added: "Mancini is very happy in St Petersburg and he's top of the Russian league."I don't think he has any intention of coming to West Ham. I don't see either Carlo or Roberto taking a job in England this season."