RIYADH, Saudi Arabia (AP) — Saudi Arabia's King Salman on Wednesday appointed his 31-year-old son Mohammed bin Salman as crown prince, placing him firmly as first-in-line to the throne and removing the country's counterterrorism czar and a figure well-known to Washington from the royal line of succession.

In a series of royal decrees carried on the state-run Saudi Press Agency, the monarch stripped Prince Mohammed bin Nayef, who had been positioned to inherit the throne, from his title as crown prince and from his powerful position as the country's interior minister overseeing security.

The newly announced Crown Prince Mohammed bin Salman already oversees a vast portfolio as defense minister and head of an economic council tasked with overhauling the country's economy. He had previously been the second-in-line to the throne as deputy crown prince, though royal watchers had long suspected his rise to power under his father's reign might also accelerate his ascension to the throne.

The young prince was little known to Saudis and outsiders before Salman became king in January 2015. He had previously been in charge of his father's royal court when Salman was the crown prince.

The Saudi monarch, who holds near absolute powers, quickly awarded his son expansive powers to the surprise of many within the royal family who are more senior and more experienced than Mohammed bin Salman, also known by his initials MBS.

The royal decree issued Wednesday stated that "a majority" of senior royal members from the so-called Allegiance Council supported the recasting of the line of succession. Saudi Arabia's state TV said 31 out of 34 of the council's members voted in favor of the changes.