The foreign minister called Khashoggi's murder a awful mistake and offered condolences to his family.
"We can feel their pain and we wish this didn't happen and I wish that this could have been avoided", he said. He appeared to be wearing Khashoggi's actual clothes, glasses and a fake beard, while also carrying a plastic bag, presumably with his own clothes.
American intelligence officials have said they intercepted communications showing that Saudi officials were plotting to lure Khashoggi back to the kingdom - an operation that was ordered by the crown prince, the officials said.
Turkey and Saudi Arabia have been at odds over what happened inside the consulate ever since Khashoggi, a critic of the Saudi monarchy, disappeared there on October 2.
Turkish media reports and officials say a 15-member Saudi team flew to Istanbul, laid in wait for Khashoggi at the consulate and then cut off his fingers, killed and dismembered the 59-year-old writer.
"In a statement Sunday, the governments said attacks on journalists are unacceptable and "of utmost concern to our three nations". Saudi Arabia has been trying to claw back global market share, especially as Iran faces new US oil sanctions beginning in November.
Videos have emerged of a Saudi suspected of being behind Jamal Khashoggi's murder walking around Istanbul in the journalist's clothes shortly after he was last seen.
UAE hails decisions taken by Saudi Arabia on Khashoggi case
But as the days dragged on and evidence of Khashoggi's death mounted, Trump's view began to shift, White House officials said. Were his remains to be found, traces of the drug may be found, asking new questions of Saudi Arabia's fist-fight narrative.
The man has been identified as Mustafa al-Madani - an official who was reportedly brought from Riyadh to Turkey to act as Khashoggi's body double.
"I cannot give you a guarantee, because I cannot predict what will happen to other suppliers", Falih said, when asked whether the world can avoid oil hitting $100 per barrel again.
"If Saudi state involvement is indeed proven, the worldwide community must stand firm in its stated resolve to insist on the highest level of investigation and punishment for those responsible - both for the perpetrators of this horrendous crime and the masterminds who ordered it".
Saudi prosecutors said 18 people had been arrested and five top officials fired for their connection to the case.
The UK, France and Germany said on Sunday that Saudi Arabia's version of Khashoggi's death needs to be supported by "facts" to be considered "credible".
Hollywood, too, has been reassessing its ties to Saudi Arabia, where the crown prince recently lifted a ban on movie theaters.
For his part, Salah Jamal Khashoggi thanked the crown prince for his condolences.
Reuters reported on Sunday it had spoken to a Saudi official who said Mr Khashoggi had died in a chokehold after resisting attempts to return him to Saudi Arabia. Speaking late Saturday after a campaign rally in Nevada, Trump said he needs to learn more about the killing and will be working with Congress on the US response. He also said Prince Mohammed was not responsible.
Germany is the world's fourth-largest arms exporter to Saudi Arabia, after the U.S., the United Kingdom, and France, Politico reported.