WASHINGTON -- For a second time this week, the White House has termed global warming a scientific fact that needs to be addressed.

On Wednesday, the Interior Department declared the polar bear a threatened species, saying it must be protected because of the decline in Arctic sea ice from global warming.

Interior Secretary Dirk Kempthorne cited dramatic declines in sea ice over the last three decades and projections of continued losses. These declines, he told a news conference, mean the polar bear is a species likely to be in danger of extinction in the near future.

Kempthorne also said, though, that it would be "inappropriate" to use the protection of the bear to reduce greenhouse gases, or to broadly address climate change.

A decision on the polar bear had been expected early this year, after environmentalists filed a lawsuit aimed at forcing a decision and a federal court on April 29 set a May 15 deadline for a decision.

Bush said Tuesday that global warming has "been more clearly defined as a problem" during his eight years in office. When asked by the Web site Politico.com if global warming is real, Bush said, "Yes, it is real; sure is."

On Monday, Republican presidential candidate John McCain said that global warming is undeniable and the country must take steps to bring it under control while adhering to free-market principles.

"For all of the last century, the profit motive basically led in one direction - toward machines, methods and industries that used oil and gas," said McCain.

"Enormous good came from that industrial growth, and we are all the beneficiaries of the national prosperity it built. But there were costs we weren't counting, and often hardly noticed. And these terrible costs have added up now, in the atmosphere, in the oceans and all across the natural world," he said.

McCain was critical of Bush White House responses to global climate change.