"... It can probably force Iran into taking RMB for their oil if they really pushed. ...".They liked their dollars and then the West started to confiscate properties and that got them more nervous.
More importantly, it doesn't really matter how much they like RMB. Recently, BHP or Rio Rinto made its first sale to China of iron ore in RMB. China told them that if you don't transact with us in RMB, we will buy it all from Russia. Guess what, Australian companies did what they need to do to get their sales across.
China can get cheap oil from Russia paid in RMB. It can probably force Iran into taking RMB for their oil if they really pushed. While GCC may control oil export market, they still don't want to loose their sales and influence to Iran and Russia. Basic economics.
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