Sen. Lindsey O. Graham (R-S.C.) on Tuesday accused the crown prince of Saudi Arabia, Mohammed bin Salman, of having Washington Post columnist Jamal Khashoggi killed and said, “This guy has got to go.”

Graham’s comments, on Fox News Channel’s “Fox & Friends,” were far less cautious than those of President Trump, who said in a pair of tweets Tuesday afternoon that the crown prince had “totally denied any knowledge” of what happened in the Saudi Consulate in Istanbul and promised answers “shortly.”

Khashoggi disappeared after a visit to the consulate two weeks ago.

“He had this guy murdered in the consulate in Turkey. Expect me to ignore it? I feel used and abused,” Graham said, referring to his previous advocacy for Saudi Arabia as a senator. “I was on the floor every time defending Saudi Arabia because they are a good ally.”

Sen. Lindsey Graham (R-S.C.) said if Saudi Arabia is responsible of the death of Washington Post contributor Jamal Khashoggi, it would be "unacceptable." (Reuters)

Graham then suggested King Salman should choose another prince to be Saudi Arabia’s presumptive leader.

“This MBS figure to me is toxic,” Graham said, referring to the crown prince, who is widely known by his initials. “He can never be a world leader on the world stage . . . This guy has got to go. Saudi Arabia, if you’re listening, there are a lot of good people you can choose, but MBS has tainted your country and tainted himself.”

The Washington Post reported last week that the crown prince had ordered an operation to lure Khashoggi back to Saudi Arabia from his home in Virginia and then detain him, according to U.S. intelligence intercepts of Saudi officials discussing the plan.

Trump has been hesitant to blame Saudi leaders. In tweets Tuesday afternoon, Trump said he had just spoken with the crown prince, “who totally denied any knowledge of what took place in their Turkish Consulate.”

He added the prince “told me that he has already started, and will rapidly expand, a full and complete investigation into this matter. Answers will be forthcoming shortly.”

Shortly after Trump’s tweets, Sen. Jeff Flake (R-Ariz.) opined that Treasury Secretary Steven Mnuchin “should not be going to Riyadh,” where he is scheduled to attend an investment conference next week.

A growing number of media companies, including CNN, have announced they will no longer participate in the event, which is scheduled to start Oct. 23.

Speaking to reporters Monday after talking to the king, Trump suggested “rogue killers” could have been responsible for Khashoggi’s death.

Trump made his comments as he announced he was dispatching Secretary of State Mike Pompeo to Saudi Arabia and pledged, “We’re going to try getting to the bottom of it very soon.”

During an interview Tuesday on Bloomberg TV, Senate Majority Leader Mitch McConnell (R-Ky.) sounded a cautious note, saying lawmakers need to find out what happened before crafting a response.