WASHINGTON (CNN) -- Attorney General Alberto Gonzales remained out of public view at the Justice Department Monday as he resumed intense preparations for crucial Senate testimony next week on the U.S. attorney firings -- the outcome of which may determine whether he can cling to his post.

Department officials acknowledged Gonzales was meeting at mid-day with department aides in advance of full-blown mock sessions in which advisers are expected to play the role of Democratic senators certain to grill him on details of the plan to fire the prosecutors, and the subsequent tangled explanations.

One Justice Department official said no final decision had been made on whether experienced outside legal experts with political experience would be a part of those sessions. The official said the private sector advisers would be called on "if it is deemed to be helpful."

Another Justice Department official confirmed that Deputy Attorney General Paul McNulty is not part of the sessions because of the need to avoid any possible coordination of the top two officials' responses on the U.S. attorney firings as an internal investigation proceeds into possible misleading congressional testimony.

Officials involved in an early prep session for the attorney general confirmed a Newsweek report that Gonzales had struggled in his first structured preparation session on March 23. An outside advisor to Gonzales acknowledged that plans to do a prospective Sunday talk show interview were scrapped after the session; the attorney general instead did a taped interview with an NBC news reporter on March 26 to defend and explain past statements on the controversial firings.

One of the Justice officials remarked that Gonzales "is getting there" as he continues his preparation for the Senate session. Gonzales has no public appearances scheduled prior to his April 17 Senate testimony. However, Monday, aides refused to fully rule out the possibility that Gonzales would participate in a public event of some type prior to his Capitol Hill appearance.

Officials noted Gonzales has now met with "over 70" of the 93 U.S. attorneys as he works to repair relations with some of his key federal prosecutors rattled by the firings of some of their colleagues. Aides say Gonzales still intends to travel to Atlanta at some point to meet with U.S. attorneys from the Southeast with whom he had earlier planned to meet before his trip had to be cancelled.

Although Justice Department officials are not yet discussing what the attorney general will tell the Senate Judiciary Committee next week, one official noted Gonzales is likely to express deep regret for the lingering controversy.