But the president has also said "we would be punishing ourselves" by cancelling arms sales to Saudi Arabia.
"The objective of (Sunday's) message broadcasted by the Saudi national media is twofold: one goal is to satisfy the domestic public opinion that Saudi Arabia and its royal family will not be humiliated and the other goal is to send a message to the US", Mitreski, researcher at the University of Sydney, told AFP.
It later clawed back some losses to close the day down 3.5 percent at 7,266.59 points.
Saudi Arabia also said it's begun an internal investigation into the disappearance Khashoggi at its Istanbul consulate and could hold people accountable if the evidence warrants it, according to a Saudi official.
After an initial silence, Riyadh said Khashoggi had left the consulate safely and then at the weekend denied as "baseless" claims that orders were given to have him killed.
"Well, nobody knows yet, but we'll probably be able to find out", Trump said in the interview with Lesley Stahl of CBS's 60 Minutes, which will air in full today.
Speaking to reporters before leaving Washington to tour hurricane damage in Florida, Trump vowed, "We are going to leave nothing uncovered". At that presser, Trump announced to the world Putin had denied any involvement in 2016 election meddling, and his intention of swallowing the horseradish. Could it be them? US markets have been rattled by rising interest rates, signs of a slowdown in the global economy and the U.S.
Tensions grew over the weekend between Washington, Turkey and Saudi Arabia over the disappearance of Khashoggi, who was a contributor to The Washington Post and who has openly criticized King Salman's son, Crown Prince Mohammed bin Salman, since his elevation to lead the country.
But concern over the disappearance has seen media organizations and a growing number of attendees pull out of a "Davos in the Desert" investment conference set for October 23-25, which has become the biggest show for investors to promote Saudi Crown Prince Mohammed bin Salman's reform vision. Trump said he would meet with Khashoggi's family.
With growing outrage over the disappearance of prominent journalist Jamal Khashoggi, Bahrain's foreign minister called for a boycott of the popular ride-hailing company Uber Technologies after the company's CEO said he will not attend a business conference in Saudi Arabia. Writer Jamal Khashoggi, vanished after he walked into the consulate on October 2.
Khashoggi has written extensively for the Post about Saudi Arabia, criticising its war in Yemen, its recent diplomatic spat with Canada and its arrest of women's rights activists after the lifting of a ban on women driving. Those policies are all seen as initiatives of the crown prince.
President Trump warned the United States would inflict "severe punishment" if Saudi Arabia was behind his disappearance. Benchmark Brent crude now trades above $80 a barrel and US gasoline prices have risen ahead of the midterm elections.
On top of the tensions with Saudi Arabia, investors are growing anxious that U.S.