President Donald Trump tweeted today that he has spoken to the Saudi king on the phone who "firmly" denied any plot to murder Khashoggi.
The controversy has troubled Saudi Arabia's traditional Western allies - many of them arms suppliers to the kingdom - and also undermined efforts by the prince, Mohammed, to present himself as the modernizing future of the kingdom.
On Oct. 2, Khashoggi entered the Saudi consulate in Istanbul, Turkey to retrieve documents for his upcoming while his fiancee waited outside.
Turkish officials allege a Saudi hit team that flew into and out of Turkey on October 2 killed and dismembered Khashoggi, who had written Washington Post columns that were critical of Saudi Crown Prince Mohammed bin Salman, also known as MBS.
Khashoggi was a USA resident who wrote columns for the Washington Post and he was critical of the Saudi government, calling for reforms.
The White House previously brushed aside threats by Saudi Arabia that it may economically retaliate for any USA punitive action imposed over the suspected murder of Khashoggi, pledging a "swift, open, transparent investigation" into his disappearance. The official said one of the men had brought along a bone saw for dismembering the body.
"If they don't buy it from us, they're going to buy it from Russian Federation or they're going to buy it from China or they're going to buy it from other countries", Trump said at a news conference on Saturday.
The battalion was named after a famous sword in the Saudi culture of Imam Turki bin Mohamed Al Saud, the founder of the second Saudi state, and the grandfather of rulers of House of Saud, who called his sword "Al-Ajrab".
Early on Tuesday, Turkish police left the Saudi consulate where Mr Khashoggi was last seen after an overnight search. "And it sounds like he and also the crown prince [Mohammad bin Salman] had no knowledge".
Saudi Arabia, meanwhile, said King Salman thanked Erdogan "for welcoming the kingdom's proposal" for forming the working group.
"The denial was very, very strong", he told reporters at the White House.
U.S. Senator Lindsey Graham, a Republican close to Trump on some issues, called the crown prince a "toxic" figure, adding, "He can never be a world leader on the world stage".
The kingdom says the allegations are "baseless" but has offered no evidence Khashoggi ever left the consulate.
The Saudi regime, for its part, has fervently denied accusations that it had anything to do with Khashoggi's disappearance and threatened to retaliate against nations that attempt to hold the kingdom accountable.
Khashoggi, who recently has been living in Virginia and writing columns for The Washington Post, hasn't been seen since October 2, when he entered the Saudi Consulate to handle paperwork for his upcoming marriage.
Turkish officials have accused Saudi agents of killing the journalist inside the consulate.
Saudi Arabia on Sunday strongly warned against any threats to exert economic sanctions or political pressure on the kingdom, saying it will respond to any action with greater action as the kingdom plays an influential and vital role in the regional and global security and economy.