Saudi Arabia replaced its powerful Energy Minister, and one of OPEC's most respected officials with a member of the royal family over the weekend, in a move that could roil global crude oil markets in the coming weeks.

Khalid al-Falih, who has served as the Kingdom's Energy Minister since 2016, will be replaced by Abdulaziz Bin Salman, a son of King Salman's son and a long-time member of the Ministry's senior team. The American-educated al-Falih, who also served as chairman of Saudi Aramco, was left out of the state-owned oil giant's plans to list as a public company earlier this month when he was removed from that role by Bin Salman. He was also stripped of his role in overseeing industrial development. 

The decision raises major questions for global oil markets, given Saudi Arabia's influence over the OPEC cartel and its ability -- largely through the leadership of al- Falih -- to get co-operation from Russia on major production cut agreements in order to control prices.

Al-Falih has also pushed backed against criticism from President Donald Trump over OPEC's production cut agreements, which are taking 1.2 million barrels from the market each day until at least the end of this year, while developing a close relationship with Russia's Energy Minister Alexander Novak,

But with Saudi Arabia losing its rank as the world's biggest producer -- to the United States -- under al Falih's watch, and global oil prices hoovering around the $60 mark despite deep OPEC cuts as the Kingdom prepares to float part of its most important asset, bin Salman's decision to bring in fresh leadership could signal a desire to drive global crude prices higher ahead of the $2 trillion IPO expected some time next year. 

Al Falih said in early July that the then trade detente between the U.S. and China, as well record American production from its recently-tapped shale fields, meant global markets could weather an extension of the output cuts.

"I have no doubt in my mind that U.S. shale will peak, plateau and then decline like every other basin in history," Al-Falih said at the time. "Until it does I think it's prudent for those of us who have a lot at stake, and also for us who want to protect the global economy and provide visibility going forward, to keep adjusting to it."

U.S. crude output has hit record highs for the past two years, thanks in part to drilling and production of shale deposits in the Permian Basin, with the Energy Department forecasting that output output from the country's seven major shale formations, including the Permian Basin and the Anadarko and Eagle Ford regions, will hit an all-time high of 8.52 million barrels per day over the summer.

Overall U.S. crude output slipped to 12.4 million barrels last week, the EIA said Thursday, from a record 12.5 million barrels in the prior seven-day period.