Mohammad Bin Salman, 31, Saudi Arabia's deputy crown prince and defense minister, was named the new crown prince instead of Muhammad Bin Nayef.
King Salman has called for public pledging of allegiance to the new crown prince in Mecca, according to local media.
The news comes amid the ongoing standoff between a number of Gulf states and Qatar. On June 5, Saudi Arabia, Bahrain, the United Arab Emirates and Egypt cut off diplomatic relations with Qatar, accusing the latter of supporting terrorist organizations and destabilizing the situation in the Middle East.
Yemen, the Maldives, Mauritius, Mauritania and the eastern-based government in divided Libya also announced a break in relations with Doha, while Jordan and Djibouti said they would lower the level of diplomatic contacts with Qatar. Senegal, Chad and Niger recalled their ambassadors from Doha.