In an interview to CNN, Pompeo was asked if he could confidently tell Khashoggi's four children that Saudi Crown Prince Mohammed bin Salman was not involved in his murder, Pompeo said he had "read every piece of intelligence" in possession of the USA authorities and concluded "there's no direct evidence linking him to the murder of Jamal Khashoggi".
Speaking from a G20 summit in Buenos Aires, Pompeo acknowledged that the humanitarian crisis in Yemen - where millions are at risk of starvation - had reached "epic proportions" but said Washington and Riyadh were offering aid.
On Friday, Mrs May delivered a "robust" message to Saudi Crown Prince Mohammed bin Salman that the United Kingdom expected his country to co-operate fully with the Turkish probe and to conduct its own investigation in a "credible and transparent" way.
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. "There is no direct reporting connecting the crown prince to the order to murder Jamal Khashoggi", Al Jazeera quoted Pompeo as saying.
Trump has said it may never be known if Prince Mohammed ordered the killing or not.
Pompeo, who declined to comment on the CIA's classified assessment, said the United States was working closely with Saudi Arabia on major foreign policy issues, including Afghanistan, and that the kingdom was a vital regional counterweight to Iran.
But Bob Corker, the outgoing Republican chairman of the Senate Foreign Relations Committee, said in an interview published on Friday that the USA needed to rein in Prince Mohammed, who was "out of control".
Mutreb, a security official who was often at the crown prince's side, is seen on security camera footage entering and leaving the consulate on the day Khashoggi was killed.
"To me, we've got a relationship with a country that's a semi-important country and a semi-important ally".
Turkey's Erdogan has said Jamal Khashoggi's murder was ordered by the highest level of Saudi leadership.
The Journal reported that Central Intelligence Agency analysis of the communication "seems to foreshadow the Saudi operation launched against Khashoggi".
Mrs May shook hands with the Saudi prince, who was also berated by French president Emmanuel Macron in a terse conversation captured on video.
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.
Friends of Khashoggi's have said that Qahtani called the journalist and raised the potential of his working for the crown prince if he would end his self-imposed exile in Virginia and return to his native country. Russian Federation and Iran back President Bashar al-Assad in Syria's civil war, while Saudi Arabia along with Western countries have backed some rebel groups.