NEW : Sources say Petraeus will resign from the military once confirmed . The decorated general is expected to be nominated to be CIA director . Comment: Analysts cite Petraeus ' experience working with the CIA in battle zones .
NEW : Sources say Petraeus will resign from the military once confirmed . The decorated general is expected to be nominated to be CIA director . Sources say Petraeus did n't want to become Joint Chiefs chairman . Analysts cite Petraeus ' experience working with the CIA in battle zones .