The Republican Sarah Palin and her officials in the Alaskan state government drew on the work of at least six scientists known to be sceptical about the dangers and causes of global warming, to back efforts to stop polar bears being protected as an endangered species, the Guardian can disclose. Some of the scientists were funded by the oil industry.

In official submissions to the US government's consultation on the status of the polar bear, Palin and her team referred to at least six scientists who have questioned either the existence of warming as a largely man-made phenomenon or its severity. One paper was partly funded by the US oil company ExxonMobil.

The status of the polar bear has become a battleground in the debate on global warming. In May the US department of the interior rejected Palin's objections and listed the bear as a threatened species, saying that two-thirds of the world's polar bears were likely to be extinct by 2050 due to the rapid melting of the sea ice. Palin, governor of Alaska and the Republican nominee for US vice-president, responded last month by suing the federal government, to try to overturn the ruling. The case will be heard in January.

Though the state of Alaska has no polar bear specialists on its staff, the governor's stance has pitted it against the combined scientific fire-power of the US Fish and Wildlife Service, the US Geological Survey, and world experts on the mammal.

In its lawsuit, Alaska said it opposed the endangered label partly because the listing would "deter activities such as ... oil and gas exploration and development". Oil companies recently bid $2.7bn (£1.5bn) for rights to explore the Chuckchi sea, an established polar bear habitat.

The threatened species status might also impede the building of an Alaskan natural gas pipeline, which Palin has called the "will of God".

Labels: corruption, environment