Republican Donald Trump is again praising former Iraqi president Saddam Hussein's ruthlessness, saying he killed terrorists "so good."

Trump was speaking at a rally Tuesday in North Carolina when he turned to the former Iraqi leader.

"Saddam Hussein was a bad guy, right? ... But you know what he did well? He killed terrorists. He did that so good," Trump said. "They didn't read `em the rights, they didn't talk. They were a terrorist, it was over."

Trump has previously said the world would be "100 per cent better" if dictators like Hussein and Libya's Moammar Gadhafi were still in power. Prior to the U.S. invasion, Iraq was listed by the State Department as a state sponsor of terrorism.

Democrat Hillary Clinton's senior policy adviser Jake Sullivan responded in a statement, "Donald Trump's praise for brutal strongmen seemingly knows no bounds."

Sullivan said such comments "demonstrate how dangerous he would be as commander-in-chief and how unworthy he is of the office he seeks."