He was welcomed by Algerian Prime Minister, Ahmed Ouyahia, and ministers at the Houari Boumediene International Airport in Algiers.
At the G20, the issue of Khashoggi's murder was also raised to Prince Mohammed by British Prime Minister Theresa May.
Before the summit, Prince Mohammed had visited the United Arab Emirates, Bahrain, Egypt and Tunisia.
In the Mauritanian capital Nouakchott early Sunday, he was welcomed by President Mohamed Ould Abdel Aziz.
They also have a record of the prince talking about "making arrangements" to deal with Khashoggi from 2017.
In an extended meeting, they discussed bilateral relations and ways to further development opportunities in the region.
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.
On a separate front for the crown prince, Argentina's state prosecutor is looking into whether criminal charges can be filed against him for alleged war crimes by the Saudi-led coalition fighting in Yemen.
Murdered dissident journalist Jamal Khashoggi in private messages referred to Saudi Crown Prince Mohammed bin Salman as a "beast", a "pac-man", who devours his enemies and raised concerns that the royal would eventually turn on his supporters, a report on Monday said. "This shows that the crown prince was witting of premeditated murder".
Asked if the Central Intelligence Agency had concluded with "high confidence" that Prince Mohammed, de facto ruler of Saudi Arabia, was involved, Pompeo said: "I can't comment on intelligence matters, CIA conclusions". In the video, Macron can be seen looking the crown prince in the eye while bin Salman nods his head and, at times, smiles.
Freeman says the crown prince still has support among many Saudis, who like that he's allowed new freedoms in the kingdom, such as letting women drive and allowing movies and music.
Saudi and Algerian businessmen met here on Monday as part of a business forum co-chaired by Algerian Minister of Industry and Mines, Youcef Yousfi, and Saudi Minister of Investment, Majid bin Abdullah al Qassabi.
The Saudi Press Agency reported after Mohammed's meeting with Modi that the crown prince pledged to meet India's oil and petroleum product needs.