Even China National Offshore Oil Corp, which primarily engages in exploration and drilling, had to build its own refinery to help the state satisfy the country's soaring petrol demand.

Such concerns have blocked new drilling in Alaska's Arctic waters since 2003, despite a steep decline in oil production in the state and intensive lobbying by oil companies.

The government has launched a national slimming campaign, led by an army of 535 trainers who are drilling a five-point exercise and healthy-eating plan into state education officials.