The Defense Clandestine Service, approved by Defense Secretary Leon Panetta last week, would work closely with the CIA at a time when the military and spy agency increasingly focus on similar threats, the senior Defense Department official told reporters on condition of anonymity.
"This is principally a realignment within the Defense Intelligence Agency," the official said. "This is basically trying to make more effective or efficient what we're already doing."
The DIA -- a Defense Department agency that is one of 16 separate U.S. government agencies conducting intelligence activities considered necessary for foreign relations and national security -- focuses mainly on collecting tactical and operational intelligence used day to day by battlefield troops.
The official downplayed concerns the Pentagon was seeking to usurp the CIA's role, saying the DIA would strive for "closer integration" with the CIA and other U.S. intelligence agencies.
DIA officers already often work out of CIA stations at U.S. embassies and gather intelligence, including on terrorism and weapons proliferation, undercover like their CIA counterparts, he said.