The problem for the Arab countries is that the market controls the sale of oil, despite their stranglehold on supply. As it stands, Middle Eastern oil contracts are sold in dollars just like North Sea Crude is sold in Pounds Sterling. Even OPEC admitted a few years ago that they can't control the denomination of oil contracts. If they want to convert their dollars to euros then fine, they'll have to convert back when the oil is sold. Plus, how absurd is it to convert from one denomination to another denomination that's selling near its high. It doesn't make sense.