As to Russia and China, what does each get out of the other? Both have swiftly aging populations, making Russia not a great place to export consumer goods to — and exporting high tech or military risks sanctions that the Chinese are particularly vulnerable to

China is desperate for oil (look at the map, they’re at the end of the very longest shipping routes from the Persian Gulf). Russia has oil in Siberia, but those wells (and pipelines) are in/on permafrost and are otherwise technically challenging. With the departure of the majors, it doesn’t appear Russia has home grown talent (not surprising, given the collapse of their educational system post-1990). The Siberians may have to ‘shut-in’ those wells. Once that’s done, re-starting might take a minimum of a decade — and the majors are long gone.

So Non-Siberian oil: Russia does not have a warm water / deep water port suitable for large tankers. They’d have to fill lighters and transfer at sea to larger vessels. All this in the Baltic — right off the coast of a number of NATO members.

As far as the renminbi/yuan Russia might get from the oil trade, given the state of the Chinese economy, having large stores of yuan doesn’t… seem the wisest investment. Read China’s Great Wall of Debt for a full explanation.

Also, look at that loooong transit from the Baltic to Chinese ports. The maritime insurance industry (90% US+UK) is refusing to cover any vessel with Russian cargo. So Russian sovereign insurance — but consider the ‘hit’ to the Russian economy if just one of those vessels were to be pulled into port for sanctions violation — or even captured by pirates — and a single vessel would be insufficient so there’ll be more at risk. The US is in charge of global overwatch (Bretton Woods Accords) but it’s not clear they’d protect a sanctions-busting vessel. If I were that captain, I’d worry particularly about the straits of Malacca…

Just my $0.02.