Mr Erdogan also questioned why Khashoggi's body had not been found even after Saudi authorities admitted to his killing.
President Erdogan delivered a sharp rebuttal of Saudi Arabia's widely criticized account that Jamal Khashoggi died in a rogue operation.
He described it as a "political murder" but stopped short of blaming the crown prince, saying: "Intelligence and security institutions have evidence showing the murder was planned".
The arrests were accompanied by an announcement that King Salman was placing his son, Mohammed, in charge of restructuring the Saudi intelligence apparatus - a move that all but ended speculation that the crown prince would be sanctioned.
And so Erdogan finally took the stage to finally give "presidential" validation to some of the stories that the Turkish press has clung to in the last two weeks.
Turkish officials say a 15-man Saudi team killed the writer at the Saudi Consulate in Istanbul. I have people in Turkey and I have people in Saudi Arabia and other places, and they're all coming back as we speak, they're heading back, he said.
Falih said the murder of Khashoggi was regrettable, adding that "nobody in the kingdom can justify it".
In order to be successful, any legal effort requires some level of cooperation from Saudi officials, which is why US businesses must use whatever influence they have.
A separate report Monday by newspaper Yeni Safak said Maher Abdulaziz Mutreb, a member of Prince Mohammed's entourage seen on trips to the U.S., France and Spain this year, made the calls from the consulate.
Jared Kushner, President Donald Trump's son-in-law and senior adviser, said the White House is still gathering facts on journalist Jamal Khashoggi's killing and wants to preserve the USA alliance with Saudi Arabia, downplaying the role of the kingdom's government in the death.
Pakistan overturns Christian woman’s blasphemy death sentence
Critics of the blasphemy law have said it is used to settle personal scores or to attack minority communities. A trial court sentenced Bibi to death on complaints that she had insulted Islam and the prophet Muhammad.
Saudi authorities did not immediately respond to a request for comment about the remarks by Trump and the Erdogan adviser but Prince Mohammed painted a different picture of relations with Turkey.
"This experience has given everyone pause.to stop, get our breath, take stock and then figure out the most appropriate way forward", David Hamod, president and CEO of the National U.S.
Turkish officials have, through multiple leaks to U.S. and Turkish media, touted the existence of audio footage of Khashoggi's killing since October 12.
Khashoggi, known for his criticism of Saudi policies, had been working as a columnist for The Washington Post.
I'll know, I think, everything in a very short period of time.
Erdogan also called for the suspects to be tried in Istanbul.
But he suggested responsibility lay higher up: "Well, the prince is running things over there more so at this stage".
Secretary of state Mike Pompeo said the Saudis had been identified in connection with the journalist's death.
Turkish state media say investigators found three suitcases, a laptop computer and clothing inside a vehicle belonging to the Saudi Consulate in Istanbul.