Oil shippers are using several tactics to hide that they're carrying Russian crude exports.. Using China's yuan instead of the dollar in trading and exchanging weapons or food for supplies are just two. Russian oil exports bought by India and then re-exported may end up in European gas stations.. ... as Europe and the US try to stem imports. At the same time, concerns are growing that India, which has snapped up Russian oil at discounted prices, has the potential to be used as a "back door" for those supplies to enter Europe ... Yuan-ruble trading volumes have soared 1,067%...