Mohammed Bin Salman wins support of Riyadh's 'allegiance council'
The 31-year-old crown prince was nominated for the position in the small hours of Wedneday morning by his father, King Salman. The 34-member bloc of senior Saudi royals known as the Allegiance Council then voted bin Salman into one of the world's most powerful seats of office with 31 votes out of 34.
The royal decree failed to mention the three members who voted against the move but one of the opposing votes is thought to have come from bin Salman himself, supposedly "as a sign of humility".
In Saudi Arabia, the line of succession has traditionally passed from brother to brother but since Salman came to power in 2015 after the death of his own half-brother, Abdullah, this has all changed.
Salman ousted his half-brother, Muqrin, as crown prince by royal decree three months into his rule and appoint his nephew Mohammed bin Nayef to the role and his son as the deputy crown prince.
Part of King Salman's latest decree has amended the Kingdom's statute of ruling, which says that only the sons and grandsons of the founding King Abdulaziz can be king and crown princes.Read more: Who is Mohammed bin Salman?
The Allegiance Council is made up from the surviving sons of King Abdulaziz, the founder of Saudi Arabia, as well as his grandsons, a son of the king (currently bin Salman) and a son of the crown prince.
Bin Salman's swift rise through the ranks of the Saudi royals has left few analysts surprised at his ascension to Crown Prince. It has long been thought that King Salman wanted his son to take the throne after his death.
Relatively unheard of before the 2015 Riyadh reshuffle, bin Salman took over the powerful defence ministry and launched a disastrous war in Yemen, which has killed at least 10,000 Yemenis and cost Saudi coffers billions of dollars.
He is also behind several economic reforms, including an austerity drive and the planned sell-off of shares in Saudi Aramco, one of the world's largest oil producers.
In taking the position, he has ousted his 57-year-old cousin, Mohammed bin Nayef, who has now sworn allegiance to the new Crown Prince.
Bin Nayef has also been replaced as interior minister, and replaced at the powerful ministry by 34-year-old Prince Abdulaziz bin Saud bin Nayef, in the most significant shake-up of Saudi politics in some years.
It is understood that King Salman, 81, has requested public displays of allegiance to be made to his son and heir.