The American has spoken out further after originally issuing a statement with joint owner George Gillett which said they wanted all the focus to be on the forthcoming matches and not off-the-pitch issues.
It is believed his frustration was borne out of a refusal by Hicks and Gillett to discuss potential transfer targets.
"After the Champions League final in Athens, Rafa made certain demands of us and we responded to those demands in the summer," said the American.
"We brought in some good players and spent more money than has ever been spent before at this club.
"We now have some crucial games coming up in the Premier League and the Champions League and we want to see if we can win these games with the players we have.
"This was the message we gave to Rafa recently and I think during the international break he must have grown a bit frustrated about this.
"We told him to concentrate on the games coming up and nothing else and I guess he didn't like that.
"But, for the time being, we just need to be focused on what happens on the pitch."
Hicks added in the Liverpool Echo: "George and I will be over in mid-December and that is the time to talk about other issues.
"It is really time for Rafa to quit talking about new players and to coach the players we have."
The Americans are expected to fly in to Merseyside to watch the home clash with arch-rivals Manchester United on December 16.