This. Those contracts werw not paid in Rubles for a good reason. Even at the height of the cold war communist countries used the USD for trade amongst themselve

This. Those contracts werw not paid in Rubles for a good reason. Even at the height of the cold war communist countries used the USD for trade amongst themselves: the Kremlin is not and never was interested in creating the sort of rules-based systems that provide an expectation of long term stability.