With Congress having targeted Iran's vital fuel imports as part of its most far-reaching sanctions package yet, observers say the Tehran government has already done much to deflect the impact of the new U.S. measures.

Under the pressure of earlier Western sanctions, Iran has over the past four years reduced its dependence on foreign imports of refined oil products from about 40 percent of its domestic needs to just under 30 percent, according to analysts. The government is seeking to reduce that figure further by expanding its capacity to refine its own oil, experimenting with alternative fuels and cutting consumption by gradually eliminating subsidies on gasoline.

In the past six months, thanks to an elaborate rationing system, domestic gasoline consumption has dropped by nearly 20 percent, official statistics show. At the same time, Iran has boosted the supply available for everyday needs and built up its strategic reserves by buying refined oil products from countries such as India, Turkmenistan and the Netherlands. Government budgets show that it has spent more than $10 billion on such purchases since 2008.

Read the entire story Thomas Erdbrink and I wrote in the Washington Post.

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