Washington ? Parts of the Endangered Species Act may soon be extinct.

The Bush administration wants federal agencies to decide for themselves whether highways, dams, mines and other construction projects might harm endangered animals and plants. New regulations, which don’t require the approval of Congress, would reduce the mandatory, independent reviews government scientists have been performing for 35 years, according to a draft first obtained by The Associated Press.

Interior Secretary Dirk Kempthorne said late Monday the changes were needed to ensure that the Endangered Species Act would not be used as a “back door” to regulate the gases blamed for global warming. In May, the polar bear became the first species declared as threatened because of climate change. Warming temperatures are expected to melt the sea ice the bear depends on for survival.

The draft rules would bar federal agencies from assessing the emissions from projects that contribute to global warming and its effect on species and habitats.

“We need to focus our efforts where they will do the most good,” Kempthorne said in a news conference organized quickly after AP reported details of the proposal. “It is important to use our time and resources to protect the most vulnerable species. It is not possible to draw a link between greenhouse gas emissions and distant observations of impacts on species.”

If approved, the changes would represent the biggest overhaul of endangered species regulations since 1986. They would 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.

The chairman of the House Natural Resources Committee, which oversees the Interior Department, said he was “deeply troubled” by the changes.

“This proposed rule … gives federal agencies an unacceptable degree of discretion to decide whether or not to comply with the Endangered Species Act,” said Rep. Nick Rahall, D-W.Va. “Eleventh-hour rulemakings rarely if ever lead to good government.”

The new regulations follow a pattern by the Bush administration not to seek input from its scientists. The regulations were drafted by attorneys at both the Interior and Commerce Departments.

Scientists with both agencies were first briefed on the proposal last week during a conference call, according to an official who asked not to be identified.

The rule changes unveiled Monday would apply to any project a federal agency would fund, build or authorize that the agency itself determines is unlikely to harm endangered wildlife and their habitat. Government wildlife experts currently participate in tens of thousands of such reviews each year.