U.S. president-elect Barack Obama is preparing to prohibit the use of waterboarding and harsh interrogation techniques by ordering the CIA to follow military rules for questioning prisoners, according to two U.S. officials familiar with drafts of the plans.

The proposal Obama is considering would require all CIA interrogators to follow conduct outlined in the U.S. Army Field Manual, the officials said. The plans would also have the effect of shutting down secret "black site" prisons around the world where the CIA has questioned terror suspects, with all future interrogations taking place inside American military facilities.

However, Obama's changes may not be absolute. His advisers are considering adding a classified loophole to the rules that could allow the CIA to use some interrogation methods not specifically authorized by the Pentagon, the officials said.

The new rules would abandon a part of President George W. Bush's counterterrorism policy that has been condemned internationally.

Obama spokeswoman Brooke Anderson did not have an immediate comment Friday about the drafted plans, which the two officials discussed only on condition of anonymity because they were not authorized to comment publicly.

No final decisions have been made about how to adjust the government's interrogation standards. Obama is still weighing whether to alter the interrogation policy by executive order during his first days in office or working with Congress through legislation.

The plans do not specifically address the issue of extraordinary rendition, the policy of transferring foreign terrorism suspects to third countries without court approval.

In private Capitol Hill meetings, CIA Director nominee Leon Panetta and Director of National Intelligence designate Dennis Blair have said Obama wants a single set of rules for interrogations. In Senate testimony Thursday, Attorney General nominee Eric Holder called the army manual "a good place to start."

The 384-page army manual, last updated in September 2006, is a publicly available document. It authorizes 19 interrogation methods used to question prisoners, including one allowing a detainee to be isolated from other inmates in some cases.

The manual explicitly prohibits threats, coercion, physical abuse and waterboarding, which creates the sensation of drowning. Holder termed waterboarding a form of torture on Thursday.

The CIA also banned waterboarding in 2006 but otherwise has been secretive about how it conducts interrogations. In the past, its methods are believed to have included sleep deprivation and disorientation, stress positions and exposing prisoners to uncomfortable cold or heat for long periods. It's also believed that some prisoners have been forced to sit in cramped spaces with bugs, snakes, rats or other vermin as a scare tactic.

Waterboarding has been traced back hundreds of years and is condemned by nations worldwide. U.S. officials waterboarded at least three top al-Qaeda operatives — including Khalid Sheik Mohammed, the mastermind of the attacks on Sept. 11, 2001 — in 2002 and 2003 because of fears that more attacks were imminent.