Jesus was answering an Italian's, a gentil's question
I see no mention in any of the four gospels where Pilate the Italian gentile was told the statement by Jesus that he will come on the clouds of heaven in power on his return.
Matthew 26:57-65 said that Jesus was only before Caiaphas the high priest, the chief priests and the entire Sanhedrin when he said, "Jesus said to him [Ciaphas]: "You yourself said it. But I say to you: From now on you will see the Son of man sitting at the right hand of power and coming on the clouds of of heaven."