Washington (CNN) Tennessee Republican Sen. Bob Corker said that the US should punish Saudi Crown Prince Mohammad bin Salman if an investigation concludes he was behind the death of Jamal Khashoggi.

"Obviously, if he's gone forth and murdered this journalist, he's now crossed the line, and there has to be a punishment and a price paid for that," the Senate Foreign Relations chairman said Sunday on CNN's "State of the Union."

Corker said he believed bin Salman directed a Saudi operation where Khashoggi, a journalist who wrote for The Washington Post, was "purposefully murdered" and that he wanted a complete investigation to bear out the facts.

Saudi Arabia admitted Khashoggi died, but claimed his death came in a fistfight with more than a dozen Saudi officials at the country's consulate in Istanbul. The Washington Post said in an article published Saturday that President Donald Trump was still praising bin Salman but acknowledged the changing accounts from the Saudis regarding Khashoggi.

"Their stories are all over the place," Trump said.

In his CNN interview, Corker said Saudi Arabia had "lost all credibility as it relates to explaining what has happened."

"I don't think anybody believes that story," Corker said.

Asked about Trump's reiteration of the Saudi story, Corker said he did not believe Trump was trying to help the Saudis cover up what happened and that he "can understand the President wanting to keep open channels."

Corker said he was still hoping for Turkey to turn over purported tapes of what happened, but that after a conversation with Secretary of State Mike Pompeo, he did not believe the US had received the tapes as of early Saturday afternoon.

Corker also sought in the interview to stress the strategic importance that Saudi Arabia would have to inform the US response.

He said King Salman "is not particularly coherent" and that bin Salman was likely to rule the country for decades. And while he described the crown prince's vision for the future as "impressive," Corker contrasted it with drastic moves in recent memory to jail high profile Saudis in the Riyadh Ritz Carlton, a flareup with Lebanon and the crown prince's "rookie mistake" in handling a blockade of Qatar.

"We also need to think about the fact that Saudi Arabia is a country that is a fairly important country," Corker said. "And so, we've got to figure out a way to have a nuanced response to this situation. But, again, if he directed it, we need to put the same types of sanctions in place that we've done with other people, who have done the same thing."

Nebraska GOP Sen. Ben Sasse said in a separate interview on the same program that the US needed to look at a wide range of responses to Saudi Arabia, including potentially cutting arms sales to the kingdom.

"I think everything should be on the table," Sasse said.

Kentucky GOP Sen. Rand Paul, a member of the Senate Foreign Relations Committee, said in an interview on "Fox News Sunday" that a full discussion of the US-Saudi relationship should be underway and called for an end to arms sales, invoking the use of US-arms by the Saudi-led coalition in Yemen and the humanitarian crisis there.

"This is not just about this journalist being killed," Paul said. "It's about the war in Yemen where tens of thousands of civilians are being killed, it's about them spreading hatred of Christians and Jews and Hindus throughout the world."

Saudi Foreign Minister Adel al-Jubeir said in an interview that aired Sunday morning on Fox News that Paul and others were announcing conclusions before all of the facts were in.

"I would respectfully urge members of Congress to wait until they have the facts and then judge the results of the facts and take positions then," he said.

The Saudi foreign minister noted at length the strategic relationship between the US and Saudi Arabia. He also said that once the investigation is over and those responsible are punished, he predicts the US-Saudi relationship will "weather" this.