As part of the restructuring which received Supreme Economic Council approval, King Salman appointed Aramco CEO Khalid al-Falih as Aramco's new chairman and as the health minister of his government.
Aramco senior vice-president Amin al-Nasser was appointed as the replacement CEO. However, Aramco also noted that he was CEO "until further notice".
Analysts believe that separating Aramco from the oil minister portfolio is the potential first step to wider reforms in the nation's oil industry.
There is also press speculation that OPEC official Prince Abdulaziz bin Salman is being lined up to replace Saudi's long-serving oil minister Ali al-Naimi, with the prince recently promoted from assistance oil minister to deputy oil minister.