President Barack Obama said Sunday that he planned to ask Congress to declare much of the Arctic National Wildlife Refuge as wilderness, including its 1.5-million-acre coastal plain, an area on Alaska's North Slope suspected to contain vast reserves of oil and gas.

The designation would forever prevent exploration and production on the coastal plain, but Sen. Lisa Murkowski, R-Alaska, said the idea would be dead on arrival in the Republican-led Congress.

Without an act of Congress, the Sunday announcement will have little practical effect in the way that the coastal plain is managed -- there would still be no drilling, while subsistence hunting and fishing could occur as before. But the decision appears to send a signal about Obama's views toward development in the Arctic, and other upcoming decisions may have more immediate effects on development in the far north.

Murkowski and the rest of the state's congressional delegation, along with Gov. Bill Walker, reacted strongly to the symbolism in the administration's announcement. In a joint statement, they said the move -- and two other anticipated announcements involving offshore drilling in the Arctic and development in National Petroleum Reserve-Alaska -- amounted to "declaring war on Alaska's future."

Murkowski, in a Sunday telephone interview from her home in Washington, D.C., called the administration's moves a "trifecta" with a cumulative impact that could harm Alaska's economy. Even though the wilderness bid will likely fail in Congress, it will reinvigorate an environmental cause that had slipped from the national consciousness, she said.

Since 1980, when the Arctic refuge was expanded from 9 million acres to 19 million acres by the Alaska National Interest Lands Conservation Act, there's been a stalemate over the coastal plain. The 1980 law left the plain in limbo, with congressional action required to open it to development or seal it permanently.

Alaska's congressional delegation and allies from oil-friendly states have spent decades trying to allow drilling. They've been opposed just as strongly by the allies of environmental groups. Democrats and Republicans could be found on either side of the issue over the years, though most of the partisans for opening the refuge have been Republican, while those seeking wilderness protection have mainly been Democrats.

Former Gov. Sean Parnell sued the Interior Department last year, seeking authority for state-run exploration of the coastal plain using three-dimensional seismic methods that avoid actual drilling but still have a physical impact. The Interior Department is fighting the lawsuit, saying the authority to explore the area for development expired in 1987.

Alaska's late Sen. Ted Stevens once complained he had become "clinically depressed" over his inability to get the coastal plain opened for drilling, even when Congress and the White House were controlled by Republicans.

A handful of Republican senators, led by John McCain of Arizona, have opposed development of the plain. McCain doesn't face re-election until 2016. Two Democrats who recently favored drilling, Mark Begich of Alaska and Mary Landrieu of Louisiana, are now gone.

The Interior Department said in a statement emailed about 7 a.m. Alaska time Sunday that it would release a conservation plan for the refuge that seeks to designate 12.3 million additional acres within the refuge as wilderness. That's on top of the already 7 million acres that are designated as wilderness within the refuge, a 19-million-acre-plus block of land in Alaska's northeast corner.

In a video, Obama said he was "proud" that the Interior Department was putting forward the new plan.

"And I'm going to be calling on Congress to make sure that they take it one step further, designating it as a wilderness so that we can make sure that this amazing wonder is preserved for future generations," Obama said in the video, where he appeared to be speaking in Air Force One.

"If Congress chooses to act, it would be the largest ever wilderness designation since Congress passed the visionary Wilderness Act over 50 years ago," the Interior Department said.

Wilderness designations require congressional approval under the Wilderness Act, a Lyndon Johnson-era law that has proved popular nationwide, though local development interests have fought against many designations.

In designated wilderness areas, road-making and industrial developments are usually banned, as are most motorized vehicles. Hunting and fishing are allowed, and in some wilderness areas, fixed-wing aircraft and motor boats can be used for transportation. In Alaska, snowmachines and other motorized vehicles are allowed in wilderness areas if local residents use them for "traditional activities."

"It's important to note that a wilderness designation would not place any new restrictions on public use or access," said Brian Glaspell, manager of the refuge.

Quick reaction

But Alaska's political leaders were quick to condemn the Sunday announcement, calling it an attack on Alaska's ability to manage its own lands. In a joint prepared statement, Murkowski, Sen. Dan Sullivan, Rep. Don Young and Walker panned the plan. All are longtime Republicans, though Walker ran as an independent.

"What's coming is a stunning attack on our sovereignty and our ability to develop a strong economy that allows us, our children and our grandchildren to thrive," said Sen. Murkowski, who chairs both the Senate Committee on Energy and Natural Resources and the appropriations subcommittee responsible for the Interior Department. "It's clear this administration does not care about us, and sees us as nothing but a territory. The promises made to us at statehood, and since then, mean absolutely nothing to them." She said Alaskans will "fight back."

Freshman Sen. Dan Sullivan called the announcement part of the Obama administration's "war on Alaska families."

"This decision disregards the rule of law and our constitution and specifically ignores many promises made to Alaska in ANILCA," Sullivan said, without elaborating on how the law was broken. "It is just one more example of President Obama thumbing his nose at the citizens of a sovereign state -- and will put Alaska and America's energy security in serious jeopardy."

Rep. Don Young called the plan "callously planned and politically motivated" and "akin to spitting in our faces and telling us it's raining outside." He also accused the Obama administration of capitulating to "the most extreme environmentalist elements."

Walker said the move comes as a major blow with the state already struggling with budget problems caused by low oil prices and would make it more difficult to produce new oil on state lands.

"This action by the federal government is a major setback toward reaching that goal," Walker said. "Therefore, I will consider accelerating the options available to us to increase oil exploration and production on state-owned lands."

A coalition of environmental groups, led by the Alaska Wilderness League, described the administration's move as a "historic announcement." In a prepared statement, they said that the U.S. Fish and Wildlife Service received nearly a million comments supporting wilderness protection and opposing oil and gas development as the agency was reviewing options for managing the refuge.

The decision by the Interior Department dates back to 2010, when it announced that it was time to renew a conservation plan for the refuge last approved in 1988, according to Mitch Ellis, the chief of refuges for Alaska. The plan's environmental impact statement says the refuge "exemplifies the idea of wilderness," with at least 47 species of land mammals, 42 of fish and 201 of birds. Because it's so huge and untrammeled, the refuge is a place "of free-functioning ecological and evolutionary processes" with unusual diversity and environmental health.

Nicole Whittington-Evans, Alaska regional director for the Wilderness Society, said the new plan wouldn't significantly change the way the refuge is managed now.

"They had a choice to recommend the coastal plain for oil and gas exploration, and they did not choose that. So for the next 15 years, the management direction will be to sustain the wilderness character and wilderness lands as they are today," she said. "We feel that there are some places that are too special to drill, and the Arctic refuge coastal plain is one of them."

Jessica Kershaw, an Interior Department spokeswoman, said the timing of the announcement stemmed from the process to develop the new conservation plan and was not part of a deliberate "trifecta" against Alaska. But she also noted that on Friday, Murkowski proposed legislation to open the refuge for petroleum development.

"So while I wouldn't necessarily directly tie one of these positions to the other, I would say that the administration certainly wants to be on record as to our position about oil and gas in ANWR," Kershaw said. "And that is why we announced our intention to recommend to Congress that 98 percent of ANWR be designated as wilderness, off limits to oil and gas development."

Reached in Washington, former Sen. Begich said the announcement was the kind of issue he fought as an otherwise Democratic ally of the administration until his defeat by Sullivan in November. He said his office acted like a "firewall" to block initiatives from the Democratic leadership that could be harmful to the state's economy.

"Half of what I did was stop these guys from moving forward," Begich said. He noted that Obama had long expressed a desire for wilderness protection in the refuge, but hadn't formally begun the process until now.

"It's not a new thing -- for six years I was able to stop it," Begich said.

A new governor's frustration

In a hastily assembled press conference Sunday afternoon, Walker said he was angry and frustrated.

"This is not a shot across the bow," he said. "It's a little more serious than that."

Even if Congress quickly rejects the wilderness designation, the impact of the administration's decision could be long-lasting, he said. It sends a message designed to kill hope for development in the refuge, he said.

Walker said he learned about some of the details of the action in an uncomfortable, hour-long phone conversation early Sunday morning with Interior Secretary Sally Jewell.

"I did not start my day well," he said. Walker said he had received no heads-up from Jewell that this sort of decision was in the works, even when they met in Washington earlier this month.

He said he expressed "strong disappointment" in the Sunday call and told Jewell, "I need to send you an invoice for the cost of doing business in Alaska, because you are taking away our ability to earn a living."

Walker is not ruling out the possibility of a state lawsuit to stop the Obama administration, but said he would pursue more "aggressive" options, such as rallying other similarly situated states and boosting public awareness about Alaska's need for new oil development.

Two other decisions in the "trifecta" suggested by Murkowski could be released the next few weeks.

The Bureau of Land Management must soon decide whether to accept ConocoPhillips' plans to develop an oil field in the National Petroleum Reserve-Alaska. The BLM, an agency of the Interior Department, manages the 23-million-acre reserve and has said it prefers a more costly development plan.

Murkowski's energy committee spokesman, Robert Dillon, said the BLM demand could not only kill the Conoco project but frighten away future oil and gas development in the reserve by setting an expensive precedent.

A second big decision expected soon from federal regulators will involve the next five-year lease sale in the U.S. Arctic Ocean, Dillon said. Large areas are expected to be removed from the sale, he said. "We don't believe it affects the existing leases, but it would have an impact going forward," he said.

"You've got a cumulative impact here," Murkowski said in the interview Sunday. "When you think about Alaska's resource opportunities for oil and gas, it is in ANWR, it's NPR-A, and it's OCS (Outer Continental Shelf), and in one week this administration is prepared to tell us go somewhere else."

Lisa Demer and Ben Anderson contributed to this story.