After initially denying the murder, Saudi Arabia acknowledged some liability but blamed his death on a "rogue" operation.
The prime minister confirmed Saturday afternoon in Argentina that he'd "directly" approached both Vladimir Putin and Mohammed bin Salman at the G20 summit.
This came after a high five between the man known as MBS and a grinning President Putin before the pair sat next to each other at the G20 conference.
After press reports that the Central Intelligence Agency was pointing the finger directly at Prince Mohammed bin Salman, Trump issued a statement saying that US-Saudi relations and oil market stability were too important to rock over the scandal.
Macron responded: 'I am anxious...
Meanwhile, bin Salman talked with world leaders as accusations swirled about the gruesome killing of Khashoggi, who was tortured before he died.
But he added: "I have read every piece of intelligence that is in the possession of the United States government, and when it is done, when you complete that analysis, there's no direct evidence linking [Prince Mohammed] to the murder of Jamal Khashoggi".
Clinton: Trump Is Part of Khashoggi Cover Up
In the briefing, Pompeo argued that the war in Yemen would be "a hell of a lot worse" if the United States were not involved. Argentina has also launched an inquiry into MBS's possible role in war crimes in Yemen and as it relates to Khashoggi.
"They exchanged pleasantries at the leaders' session as he did with almost every leader in attendance", the White House official said on Friday.
Secretary of State Mike Pompeo, however, separately met with Saudi Foreign Minister Adel al-Jubeir, the State Department said.
The Wall Street Journal (WSJ) also reported on Friday that in August 2017, MBS had told associates that if his efforts to persuade Khashoggi to return to Saudi Arabia were unsuccessful, "we could possibly lure him outside Saudi Arabia and make arrangements", according to the assessment.
European Union leaders urged G-20 participants to address concerns about journalist safety and the Saudi-backed war in Yemen.
Theresa May, the first British prime minister to visit the Argentine capital, told British media she wanted to "be robust" in discussions with Salman over the war in Yemen and Khashoggi's death.
She promised to push for a transparent, credible investigation that would ensure "confidence in the outcome of it".
China "will continue to stick together with the Arab country on issues involving their core interests", Xinhua quoted Xi as telling the prince.