The drop in the Tadawul exchange in Riyadh happened Sunday, the first day of trading.
Trump declined to provide an example of an action he was considering taking to punish Saudi Arabia, saying only that "there are many things we could do".
He also brushed aside the apparent threats from the oil-rich kingdom of economic retaliation if the US were to impose strict measures and said Mnuchin intends to attend the Saudi conference to address terrorist financing.
The US president issued his firmest statement yet over the disappearance of Washington Post contributor Jamal Khashoggi.
According to Independent Khaled bin Farhan al-Saud, a Saudi prince living in exile in Germany told foreign media that the Saudi authorities had planned to kidnap him as well before Jamal Khashoggi disappeared.
At Saudi Arabia's request, it's establishing a joint working group with Turkey to investigate Khashoggi's fate, Ibrahim Kalin, Erdogan's spokesman, told reporters on October 11.
New Zealand could put its business interests with Saudi Arabia at risk if it strongly speaks out soon against the suspected murder of journalist Jamal Khashoggi at Saudi Arabia's consulate in Turkey, an Otago academic believes. "Investors do not feel solid in Saudi yet, so it's easy for them to take back their funds".
"The kingdom confirms its categorical rejection of any threats and attempts to harm it by threatening to impose economic sanctions or the exercise of political pressure", the official continued, adding that the Saudi economy is "vital and influential" in the global economy. But Trump has said he does not want to halt a proposed $110 billion arms sale to Saudi Arabia because, he maintained, it would harm US manufacturers.More news: Keep Jimmy Butler away from the Lakers
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"By leaking information on the case in a controlled manner, Turks have signaled their willingness to confront the Saudis if they have enough worldwide support, particularly from the West", said Gonul Tol, director of the Middle East Institute's Center for Turkish Studies in Washington.
Aldakhil added that Saudi arms purchases from the us and other trade could be at risk as well.
"The Kingdom of Saudi Arabia extends it appreciation to all, including the United States administration, for refraining from jumping to conclusions on the ongoing investigation".
Khashoggi, a Washington Post columnist and permanent U.S. resident, had fallen out of favor after previously enjoying close ties with the Saudi royal family.
Saudi King Salman called President Recep Tayyip Erdoğan, thanking him for the recently formed joint Turkish-Saudi working group to investigate the disappearance of journalist Jamal Khashoggi, who is feared to have been murdered by a team of Saudi agents in the kingdom's Istanbul consulate.
He told CBS: "We're going to get to the bottom of it".
Turkish and foreign media who have camped outside the consulate all week noticed the motorcade arriving on Friday but it had not been immediately clear who were the Saudi personnel entering the consulate were.
Dimon follows almost a dozen other executives from the technology, media and entertainment industries who have backed out of the Future Investment Initiative conference, nicknamed "Davos in the Desert".
Ford Motor Co. confirms that Executive Chairman Bill Ford will not attend. "Certainly our involvement in Yemen with Saudi Arabia will be effected".