A U.S. federal decision on the species status of polar bears has environmentalists and businesses arguing over the issue of global warming, observers say.

The Interior Department was in the U.S. District Court in Washington Wednesday defending its decision to classify polar bears as "threatened" rather than "endangered" despite ongoing shrinkage of the bears' sea ice habitat, the Los Angeles Times reported Thursday.

Several environmental groups have sued to change the bears' status to endangered, which would pressure the Obama administration to attack the sea ice problem at its source: the greenhouse gases emitted by petroleum, coal and manufacturing companies that scientists say are a major contributor to climate change.

The government's decision to retain the bears' "threatened" status comes amid industry pressure, environmentalists say.

"There is a pronounced push-back from industry because they rightly see that they will have to modify or mitigate their activities to comply with the laws," said Andrew Wetzler of the Natural Resources Defense Council, one of the groups suing to change the polar bears' status.

The Interior Department's "threatened" listing of the bears includes the so-called "4d" exemption, which excludes greenhouse gases from being regulated as a threat to a species.

Industry groups including the American Petroleum Institute, the U.S. Chamber of Commerce and the National Mining Assn., are fighting to keep the exemption.

"It's based upon the position that the science doesn't exist to draw a link between a particular activity, industrial or otherwise, and an identifiable incremental effect on sea ice," Richard Ranger, senior policy adviser for the API, said.