Republican presidential front-runner Donald Trump said Sunday that the U.S. needs to deploy techniques like waterboarding "at a minimum," if its going to be successful in fighting terror groups -- something he said he would do as president.

Appearing on CNN Sunday, when asked about his proposal during Saturday night's GOP debate in New Hampshire, Trump said, "I'd go through a process and get it declassified frankly ... certainly waterboarding at a minimum."

The billionaire businessman said that the tactic, which has been deemed torture, is justified in the case of ISIS and similar groups because of the brutal ways in which they act.

"They're chopping off heads of Christians and many other people in the Middle East," said Trump, according to CNN. They're chopping heads off, they laugh at us when they hear we're not going to approve waterboarding and then they'll have a James Foley and others where they cut off their heads."

However, Trump also said that waterboarding is permissible because of the information it yields -- something experts say is untrue. "You can say what you want I have no doubt that it does work in term of information and other things," Trump said during the CNN interview.

Trump also appeared on ABC's This Week on Sunday, where he was asked by host George Stephanopoulos, "Do we win by being more like them?" Trump answered: "Yes. I'm sorry. You have to do it that way."

During Saturday's debate, Trump said he would use the banned tactic to extract information from potential terrorists. "Not since medieval times have people seen what’s going on," Trump said, The Washington Post reported. "I would bring back waterboarding, and I’d bring it back a hell of a lot worse than waterboarding," he added, without noting what constitutes "worse" in his view.