Sen. Carl Levin (D-Mich.) pressed John Brennan on whether waterboarding is torture. President Obama's nominee to lead the CIA would not give a yes or no answer, but he said that waterboarding would never be reintroduced on his watch. He also said he was unsure whether the use of harsh interrogation techniques had led to useful intelligence.

Saying he wasn't a lawyer, Brennan noted that "the attorney general has referred to waterboarding as torture." But, he said, "the term has a lot of legal and political implications."

Brennan did say clearly that "waterboarding never should have been employed, and never will be if I have anything to do with it."

Earlier, Sen. Saxby Chambliss (R-Ga.) asked Brennan whether valuable information had come from the use of enhanced interrogation techniques.

"I clearly had the impression" in the past "that there was valuable intelligence that came out of those interrogation sessions," Brennan said. But a Senate Intelligence Committee report calling the techniques ineffective "raises questions about the information that I was given at the time, the impression I had at the time," he said.

"At this point, senator," he said, "I do not know what the truth is."