The dismissal of Falih - who has been the worldwide face of the kingdom's oil policy since his appointment in 2016 - caps 10 days of changes to senior positions in the kingdom's energy sector. Markets reacted positively to this announcement on hopes that production cuts could be extended, particularly following comments from the Prince that the OPEC+ alliance will be in place for the long term.
The oil ministers of Oman and Iraq earlier told reporters in Abu Dhabi that it was too early to assess whether deeper cuts were required to support oil markets at a time of global recession concerns due to the US-China row.
Saudi Arabia wants to enrich uranium in the future to fuel its planned nuclear power programme, its energy minister said on Monday, a sensitive step that could complicate U.S. companies' involvement in the plan.
"He is the institutional memory of the Saudi oil policy and OPEC".
The Schork Report Publisher Stephen Schork on the oil market and the future of the Saudi Aramco IPO.
"The price reaction is muted because we don't expect a strong change".
In April the head of the IAEA said his agency was asking Saudi Arabia to agree to safeguards on nuclear material that could arrive by the end of the year for its first atomic reactor.
In his first public appearance as minister, Prince Abdulaziz signaled no radical change in Saudi oil policy.
The 25-nation OPEC+ group, dominated by the cartel's kingpin Saudi Arabia and non-OPEC production giant Russian Federation, agreed to reduce output in December 2018.
He replaces veteran official Khalid al-Falih as the world's top crude exporter accelerates preparations for a much-anticipated stock listing of state-owned oil giant Aramco, expected to be the world's biggest. The government also separated the ministry of industry and mineral resources from the energy portfolio, removing Falih's oversight of industrial policy.
Even with more time to focus on the oil market, Prince Abdulaziz will confront the same tough challenges as Al-Falih.
However, while oil markets have reacted positively to the potential of an extension of current OPEC cuts, the challenges for the oil market remains on the demand side amid the slowdown in the global economy stemming from US-China trade wars. Now the trade war is putting pressure on demand, prompting analysts to ask whether further output cuts will be necessary next year.
Rising costs of crude typically result in higher prices at the pump, with the effect usually felt by consumers six weeks after the initial oil hike.
But in the three years since Prince Mohammed was appointed crown prince, he has upended convention in the absolute monarchy with his aggressive drive to reshape the conservative nation according to his vision.