Here's an article that 'splains it a little more.
When will we buy oil in euros?
When it comes to the global oil trade, the dollar reigns supreme. But it has a challenger, writes Faisal Islam
Sunday February 23, 2003
The Observer
Whether the price of oil is surging to new highs, as it is today, or slumping, as is predicted after a war in Iraq, there is one enduring constant: the dollar sign.
Oil trading, whether from Norway to the Netherlands, Britain to Bermuda, or Bahrain to Bangladesh, operates through the US greenback.
The oil-dollar nexus is one of the foundations of the world economy that inevitably filters through to geopolitics. Recycling so-called petrodollars, the proceeds of these high oil prices, has helped the United States run its colossal trade deficits. But the past year has seen the quiet emergence of the 'petroeuro'.
Effectively, the normal standards of economics have not applied to the US, because of the international role of the dollar. Some $3 trillion (£1,880 billion) are in circulation around the world helping the US to run virtually permanent trade deficits. Two-thirds of world trade is dollar-denominated. Two-thirds of central banks' official foreign exchange reserves are also dollar-denominated.
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