President Trump on Friday said he will allow Defense Secretary James Mattis to decide whether the U.S. should bring back enhanced interrogation methods, despite his own belief that torture works.

"We have a great general who has just been appointed secretary of defense and he has stated publicly that he does not necessarily believe in torture," Trump told reporters during a joint press conference with British Prime Minister Theresa May.

"I don't necessarily agree, but I will tell you that [Mattis] will override because I'm giving him that power," Trump said. "I am going with our leaders and we're going to win with or without — but I do disagree."

Trump's sweeping statement not only gives Mattis, a former top U.S. military commander, an effective veto over any effort to revive "enhanced interrogation techniques," it also places his judgment above that of CIA Director Mike Pompeo.

During his confirmation hearing, Mattis provided a written response to the Senate Armed Services committee that was unequivocal about the use of waterboarding as far as the military goes.

Mattis said, "I fully support using the Army Field Manual as the single standard for all U.S. military interrogations."

The 2016 National Defense Authorization Act includes language limiting interrogation techniques to those in the Army Field Manual, which does include waterboarding or other forms of enhanced interrogation.

While Pompeo was not as emphatic in his public confirmation testimony, Sen. John McCain said the CIA director repeatedly committed to him that he would "comply with the law that applies the Army Field Manual's interrogation requirements to all U.S. agencies, including the CIA."

During an interview with ABC that aired this week, Trump said he had spoken with people "at the highest level of intelligence" within the past day who told him that torture does work, but that he will ultimately defer to Mattis and Pompeo and stay within the bounds of law.

"Now, that being said, I'm going with Gen. Mattis. I'm going with my secretary because I think Pompeo is going to be phenomenal. I'm going to go with what they say," he continued. "I will rely on Pompeo and Mattis and my group. If they don't want to do, that's fine. If they do want to do, then I will work toward that end," he said.

It was CIA agents, not members of the U.S. military, who waterboarded terror suspects in the wake of 9/11 at "black sites" outside the United States. That included Khalid Sheik Mohammad, the accused mastermind of the attacks, and Abu Zubaydah, the CIA's first detainee.

Details of the covert CIA program were disclosed in a 2014 Senate Intelligence Committee report.

The law requires the Army Field Manual to be updated to ensure it "complies with the legal obligations of the United States and reflects current, evidence-based, best practices for interrogation that are designed to elicit reliable and voluntary statements and do not involve the use or threat of force."