Updated

With the Bush administration on the verge of relaxing regulations protecting endangered species, Democratic leaders are looking at ways to overturn any last-minute rule changes.

The Bush administration has until Friday to publish new rules in order for them to take effect before President-elect Barack Obama is sworn in. Otherwise, Obama can undo them with the stroke of a pen.

A rule eliminating the mandatory, independent advice of government scientists in decisions about whether dams, highways and other projects are likely to harm species looked likely to meet the deadline, leaving the only chance for a quick reversal to Congress.

Drew Hammill, a spokesman for House Speaker Nancy Pelosi, D-Calif., said the House will be looking at ways to overturn the final endangered species rules and other one-minute-to-midnight regulations.

"The House, in consultation with the incoming administration and relevant committees, will review what oversight tools are at our disposal regarding this and other last-minute attempts to inflict severe damage to the law in the waning moments of the Bush administration," Hammill said.

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A Nov. 12 version of the final endangered species rules obtained by The Associated Press has changed little from the original proposal, despite the more than 250,000 comments received since it was first proposed in August.

The rules eliminate the input of federal wildlife scientists in some endangered species cases, allowing the federal agency in charge of building, authorizing or funding a project to determine for itself whether the project is likely to harm endangered wildlife and plants.

Current regulations require independent wildlife biologists to sign off on these decisions before a project can go forward, at times modifying the design to better protect species.

The regulations also bar federal agencies from assessing emissions of the gases blamed for global warming on species and habitats, a tactic environmentalists have tried to use to block new coal-fired power plants.

But the Bush administration feels that endangered species laws should not be used to regulate greenhouse gases.

Tina Kreisher, an Interior Department spokeswoman, could not confirm whether the rule would be published before the deadline, saying only that the White House was still reviewing it. She said it was possible more changes could be made.

"We started this; we want to finish this," Kreisher said.

If the rules go into effect before Obama takes office, they will be difficult to overturn since it would require the new administration to restart the rule-making process.

Congress, however, could reverse the rules through the Congressional Review Act, a law that allows review of new federal regulations.

It's been used once in the past 12 years, but some Democratic lawmakers have said they may employ it to block the endangered species rules and other last-minute regulations by the Bush administration.

"This is a shining example of the brash giveaways to industry we expect to see during the Bush administration's final days, and a new Congress will stand at the ready to use our authority to overturn this and other harmful rules," said Rep. Edward Markey, D-Mass., chairman of the House select committee for energy independence and global warming.

The Bush administration has made no secret of its intent to complete the endangered species changes quickly.

When the proposal was first announced in August, the public was given 30 days to comment. That period was doubled after Democratic lawmakers pressed for more time.

Then, last month, the head of the endangered species program corralled 15 experts in Washington to sort through 200,000 comments in 32 hours.

"This is definitely lightning quick," said John Kostyack, executive director of the National Wildlife Federation's Wildlife Conservation and Global Warming initiative. "I would be surprised that they spent all this time rushing it through if it wasn't greased."

If successful, the Bush administration will accomplish through rules what conservative Republicans have been unable to achieve in Congress: ending some environmental reviews that developers and other federal agencies blame for delays and cost increases on many projects.

Supporters of the changes also expected it to be finalized later this week.

The Pacific Legal Foundation, which advocates for property rights, urged that the rules be approved.

"Litigious activists have used the Endangered Species Act to fight projects," Reed Hopper, the foundation's principal attorney, said in a statement. "The administration's current proposal is a step toward curbing these abuses."