Sen. Lindsey Graham, R-S.C., emerged from a closed-door briefing led by CIA Director Gina Haspel on Tuesday more convinced than ever that Saudi Crown Prince Mohammed bin Salman was "complicit" in the killing of journalist Jamal Khashoggi.

The senior senator from South Carolina, and a close ally of President Donald Trump, told reporters on Capitol Hill that "there's not a smoking gun, there's a smoking saw" connecting the crown prince to Khashoggi's slaying.

His and other senators' remarks appeared to contradict senior Trump administration officials — as well as Trump himself — who have claimed that no "direct evidence" links the Saudi leader to the killing.

"The crown prince is a wrecking ball. I think he's complicit in the murder of Mr. Khashoggi to the highest level possible. I think his behavior before the Khashoggi murder was beyond disturbing. And I cannot see him being a reliable partner to the United States," Graham said after the briefing.

"If the Saudi government is going to be in the hands of this man for a long time to come, I find it very difficult to be able to do business because I think he's crazy, I think he is dangerous, and he has put the relationship at risk."

Sen. Bob Corker, R-Tenn., told journalists he has "zero question in my mind that the crown prince, MBS, ordered the killing, monitored the killing, knew exactly what was happening, planned it in advance. If he was in front of a jury he would be convicted in 30 minutes. Guilty. So, the question is what do we do about that."

Sen. Bob Menendez, D-N.J., agreed with Corker, "That was my view before this briefing, and it is certainly my view now."

Corker has been an outspoken critic of Trump, and is retiring from the Senate at the end of his term.

Khashoggi, a Washington Post columnist and critic of the Saudi royal family, was killed and allegedly dismembered in the Saudi Consulate in Istanbul, in early October. The Saudi foreign minister eventually admitted that the killing was an "unfortunate accident," but the kingdom has maintained that the crown prince himself was not involved.

Graham vowed to send a bipartisan statement before the end of the 115th Congress asserting that the crown prince was involved in Khashoggi's murder.

"I cannot support arms sales to Saudi Arabia as long as he's gonna be in charge of this country," Graham added.

The White House did not immediately respond to CNBC's request for comment on the senators' remarks.

Trump, citing the importance of putting "America first" in an exclamation-point-filled statement on the subject in November, concluded of bin Salman's alleged involvement in the killing: "Maybe he did and maybe he didn't!"

Secretary of State Mike Pompeo and Defense Secretary James Mattis later backed up Trump's position, reportedly telling senators in a prior closed session that there was no direct evidence to conclude that the crown prince was involved.

Graham dismissed that view as "following the lead of the president" on Capitol Hill Tuesday.

"You have to be willfully blind not to come to the conclusion that this was orchestrated and organized by people under the command of MBS and that he was intricately involved in the demise of Mr. Khashoggi," Graham said.