Wagner, who took on the role of CEO and co-owner at the studio with her longtime business partner Tom Cruise, said she planned to return to a full-time producing role under her own production label.
She will remain attached to UA's existing projects, which includes the WWII thriller Valkyrie that has been brought forward to December 26 release slot. Cruise will maintain his ownership stake in UA and it is understood will continue to make films with Wagner.
The move had been expected in recent weeks and it is understood that Wagner's slow pace in greenlighting projects was a factor. Only the flop Lions For Lambs and Valkyrie have gone into production since she took the reins nearly two years ago.
By contrast parent company MGM has greenlit a slew of new projects since rebooting itself as a production entity under the stewardship of production chief Mary Parent.
Warning signs first emerged in July when Dennis Rice left as president of worldwide marketing and publicity. Last week Jeff Kleeman departed as executive vice president of production after less than one year in the position.