A showdown between President Umaru Yar’Adua and powerful Nigerian oligarchs over his moves to break their grip on the lucrative fuel importation business has led to the country’s worst petrol shortages in years.

Nigerian commentators see the dispute as the biggest test yet of the ability of the president’s two-year-old administration to confront business and political elites with a vested interest in opposing his plans to remove key bottlenecks in the economy.