"Our intention is ... to let the interim directive expire," Agriculture Undersecretary Mark Rey said Wednesday.
Environmentalists said the decision strengthens the rule put in place during the Clinton administration's final days and later upheld by a federal appeals court.
"It means the roadless rule will become the operative law for the Forest Service," said Mike Anderson of The Wilderness Society.
A spokesman for the timber industry played down the decision, noting that even under the interim rule, no new roads have been built in national forests.
"So in fact we've had ... the roadless rule in place for the last 21/2 years," said Chris West, vice president of the American Forest Resource Council, an industry group.
Although Rey and other officials have said they support the principles behind the roadless rule, the administration declined to defend the rule in court. That led environmental groups to intervene in an Idaho case brought by the Boise Cascade Corp. and a coalition of Western logging and snowmobiling interests.
A divided 9th U.S. Circuit Court of Appeals upheld the rule in December, saying the Forest Service had met all the legal requirements in developing the road ban, which covers nearly one-third of the nation's forests.
Rey said the administration plans to develop a permanent set of guidelines for roadless areas once the interim rule expires June 14.
"We'd like to see something proposed this year," he said.
The interim rule, issued in late 2001, allows the Forest Service chief to make decisions on development in roadless areas while court cases challenging the rule are pending. As a practical matter, Forest Service Chief Dale Bosworth has not permitted any road construction in areas where it would have been prevented by the Clinton-era rule.
Congressional supporters of the roadless rule plan legislation that would give the Clinton-era rule the force of law. Reps. Jay Inslee, D-Wash., and Sherwood Boehlert, R-N.Y., are leading efforts in the House, while Sens. Maria Cantwell, D-Wash., and John Warner, R-Va., are pushing the bill in the Senate.
Forest Service background on roadless rule: www.roadless.fs.fed.us