ALLEGIANCE COUNCIL
When the king dies or is no longer be able to rule, the 34-member Allegiance Council, a body representing each line of the ruling family to lend legitimacy to succession decisions, would not automatically declare MbS the new king.
Even as crown prince, MbS would still need the council to ratify his ascension, one of the three Saudi sources said. While the council accepted King Salman's wish to make MbS crown prince, it would not necessarily accept MbS becoming king when his father dies, especially given that he sought to marginalise council members.
Officials in Riyadh did not respond to a request for comment.
The Saudi sources say MbS has destroyed the institutional pillars of nearly a century of Al Saud rule: the family, the clerics, the tribes and the merchant families. They say this is seen inside the family as destabilising.
Despite the controversy over Khashoggi's killing, MbS is continuing to pursue his agenda.
Some insiders believe he built his father a new but remote Red Sea palace in Sharma, at the Neom City development site -- thrown up in a record one year at a cost of $2 billion -- as a gilded cage for his retirement.
The site is isolated, the closest city of Tabouk more than 100 km (60 miles) away. Residence there would keep the king out of the loop on most affairs of state, one of the sources close to the royal family said.
Officials in Riyadh did not respond to a request for comment.