Saudi Arabia is reportedly currently conducting talks with China about pricing some of its oil sales in Chinese Yuan, causing the currency to increase in value.
Talks have been on and off for the past 6 yrs between the Gulf kingdom and China, but they've recently accelerated due to Saudi Arabia's displeasure with the US.
China is swooping in to deepen ties with America's friends and foes in the Middle East. Beijing buys nearly half of its oil from Arab states--with Saudi Arabia topping the list. But as close as these links get, China isn't likely to entangle itself in Middle East conflicts and can't bring the same security guarantees that the US can to the region.
China has always prioritized relations with Saudi Arabia and the Middle East because they share similar visions and core values, standing firm against unilateralism and bullying. Saudi Arabia is a great partner for Beijing--Riyadh soundly rejects interfering in PRC domestic affairs, champions the one-China principle, and supports Beijing on Taiwan and Xinjiang.
Poor relations with Saudi Arabia and the UAE are completely Biden's fault. Even after the UAE was attacked by Iran-backed Houthi terrorists, Biden failed to support an important American ally, choosing instead to prioritize relations with Iran. He hasn't even spoken directly to MBS since taking office.
The Gulf leaders have shunned Biden because they're unhappy with him calling out their human rights abuses. The Saudis and UAE are playing hard to get in order to extort concessions on the war in Yemen and the killing of Jamal Khashoggi. The president must stand firm; oil prices shouldn't be prioritized over human rights.