Hammond said on Reading's official website: "He has arguably been one of the club's best ever signings, in terms of what he produced on the pitch, the value for money he gave us, and now the fact he has been sold for a club-record fee.
"The point in time arrived where it was the right opportunity for him and the right deal for the club as well.
"I have already offered my best wishes and I am sure the supporters will be doing the same to a player who rightly earned their respect.
"Lastly, it is important from my own point of view to say that Wolves, and in particular their chief executive Jez Moxey, have been a pleasure to deal with and very straightforward. They have got themselves a top player."