The closed-door meeting between two leaders, which lasted 50 minutes, was held on the sidelines of the G20 Leader's Summit in the capital Buenos Aires. Trump administration officials on Sunday continued to stress that point and emphasised the importance of the United States' maintaining a close relationship with Saudi Arabia.
Saudi Crown Prince Mohammed bin Salman was warmly received and was seen later on enjoying the cultural event with heads of G20 and more than 1,000 elite personalities from Argentinian society.
Pompeo reiterated his insistence that there was no "direct evidence" that Saudi Crown Prince Mohammed bin Salman (better known as MBS) ordered the killing of Khashoggi, who lived in the USA and wrote for The Washington Post.
Trump has said it may never be known if Prince Mohammed ordered the killing or not.
"We have no intention to damage the Saudi royal family or the Kingdom of Saudi Arabia, but revealing the truth about the murder with all its aspects and putting all whose responsible on a trial would benefit the Saudi Arabia as well", he said.
But Bob Corker, the outgoing Republican chairman of the Senate Foreign Relations Committee, said in an interview published on Friday that the United States needed to rein in Prince Mohammed, who was "out of control".
Canada has been outspoken on human rights in Saudi Arabia, which has retaliated by breaking off diplomatic relations and vowing to end trade.
The Trump administration faces tremendous domestic and global pressure to review its relationship with Saudi Arabia after Saudi journalist Jamal Khashoggi's murder at the Saudi consulate Istanbul in October this year.
However, Moscow has also fostered strong ties with Saudi Arabia's regional arch foe Iran.
Turkey's Erdogan has said Jamal Khashoggi's murder was ordered by the highest level of Saudi leadership.
Earlier in November, the Wall Street Journal said that excerpts of the assessment it had not previously reported state that the Central Intelligence Agency has "medium-to-high confidence" that Prince Mohammed "personally targeted" Khashoggi and "probably ordered his death" - but added: "To be clear, we lack direct reporting of the Crown Prince issuing a kill order". Trump issued a statement that included defence of the kingdom as a "great ally" and refusal to assign blame to the prince, saying "maybe he did and maybe he didn't" order the killing.
A meeting with Turkish president Recep Tayyip Erdogan is expected to focus on Ankara's investigation into the death of Khashoggi at Saudi Arabia's consulate in Istanbul in October. Al-Qahtani was sanctioned by the White House last month for his involvement.
But Trudeau said his biggest concern was the situation in Yemen, where a humanitarian crisis is unfolding in the midst of a long, destructive war between a Saudi-led coalition supporting the Yemeni government and Iranian-backed Houthi rebels.