The comments came after US President Donald Trump said he would seek "severe punishment" against Saudi Arabia if the country was found to have murdered Khashoggi.
"I am planning on going at this point", Mnuchin said on Friday of the investment conference, which is slated to start in Riyadh on 23 October. The index recovered some ground later to close 3.5% down.
But the president has also said "we would be punishing ourselves" by canceling arms sales to Saudi Arabia.
Khosrowshahi's decision not to go "unless a substantially different set of facts emerges" could put him and Uber in an awkward spot because Saudi Arabia's Public Investment Fund owns about a 5.6 per cent stake in the privately held ride-hailing app.
Anti-Saudi sentiment in the U.S. Congress could conceivably raise pressure to pass the No Oil Producing and Exporting Cartels Act, which would end sovereign immunity shielding OPEC members from U.S. legal action. He'd become an outspoken critic of the country's powerful Crown Prince Mohammed bin Salman. He brazenly said Thursday that he was not willing to throw away billions of dollars in military deals with Saudi Arabia. One can only hope that what looks to be the brutal pre-meditated murder of Jamal Khashoggi, a US resident, might finally provoke something other than praise for Saudi Arabia and its de-facto ruler.
Turkey has yet to publish any evidence of him being slain, though surveillance footage around the consulate shows a convoy of vehicles with diplomatic license plates leaving the Saudi Consulate for the consul's home in Istanbul a little under two hours after Khashoggi's arrival.
Florida Republican Marco Rubio tells CNN's "State of the Union" that he doesn't think any USA government officials "should be going and pretending as it's business as usual, until we know exactly what's happened here".
GCC Secretary General said that what are being circulated in some Arab and global media are false accusations and claims that are not based on facts and are aimed at harming Saudi Arabia.
Trump visited the kingdom on his first overseas trip as president and has touted arms sales to Saudi Arabia.
The Sultanate of Oman has confirmed its support for the efforts of Saudi Arabia to clarify the truth regarding the disappearance of the Saudi citizen Jamal Khashoggi, calling for verification before issuing any judgements.
According to Rubio, the USA rightly condemns corrupt leaders like Vladimir Putin in Russia, Bashar Assad in Syria and Nicolás Maduro in Venezuela and should absolutely condemn the Saudi regime if the allegation is proven true - regardless of whether we are foes or allies.
Turkish authorities say a team of Saudis killed Khashoggi, and USA intelligence intercepts show Saudi officials discussing an operation to lure Khashoggi - a Saudi citizen who had been living in the U.S. - back to Saudi Arabia from his home in Virginia and detain him.
The German, French and British foreign ministers said in a joint statement Sunday that defending freedom of expression and ensuring protection for journalists are key priorities and that they are "treating this incident with the utmost seriousness".