Shah of Iran (A major US ally) independently, also had trade agreements with China, Russia (including light arms with Russia), Eastern European countries, and even Cuba.  As a matter of fact China was not invited in Asian Olympics (and international Olympics since 1952), but in 1974 the shah invited China to participate in the Asian games. 

Israel and most Persian gulf countries trade agreements with the U.S. is relatively higher compared to that of with Russia and China.  China’s economy is also tightly dependent of US and US is their largest trade partner by highest margin as well. China’s trade with Russia is about 1/10th of what it is with US. What China has started to do in the past couple of decades is what western capitalist countries do and have been doing.  

Biden even doing a favor to China by allowing China to purchase Iranian oil at 40% discount and Russian oil at 30% discount. By looking the other way as both countries are under sanctions. This created excess surplus of oil and oil capacity in China. I see this as a great deal between China and US, especially with the return of the favor by China for accommodating the so called peace agreement between Saudi and Iran.  

Don’t even be surprised if China adds 10_20% mark up and sells that oil to US or even Israel, still a nice discount. Yeah implausible, but you never know.