Commerce Secretary Wilbur Ross listens as Vice President Pence, not pictured, speaks at Commerce Department headquarters in Washington on July 16. (Andrew Harrer/Bloomberg)

Commerce Secretary Wilbur Ross took a first step to expanding the trade war to uranium Wednesday, saying he would launch an investigation into whether quotas should be used to restrict imports in the name of national security.

But utilities with nuclear plants fear such actions would raise the cost of electricity and nuclear experts said the military already has stockpiles big enough to last for decades.

“Our production of uranium necessary for military and electric power has dropped from 49 percent of our consumption to 5 percent,” Ross said in a statement. That change took place over 30 years, he said.

Much of the imported uranium comes from friendly nations. In 2017, Canada and Australia provided more than half of U.S. uranium consumption, according to the Commerce Department. Russia provided 16 percent.

Ross announced the investigation six months after a petition by two uranium mining companies, Energy Fuels and Ur-Energy, seeking quotas under Section 232 of the 1962 trade law that deals with national security. The companies want the Trump administration to cordon off 25 percent of the U.S. uranium market for U.S. companies.

The commerce secretary noted that three U.S. companies with mining operations have been idled in recent years. The two mining companies that filed the petition had laid off more than half their workforce over two years and said mines couldn’t be reopened quickly if needed.

Independent nuclear experts said that the U.S. military can rely on large stockpiles. The United States has 574.5 metric tons of highly enriched uranium, according to the International Panel on Fissile Materials. A 2015 Energy Department study on security of supply said “new sources of fuel for naval reactors will be needed in approximately 2060.” The United States is seeking to reduce the number of nuclear warheads worldwide, so there is little need for uranium imports for U.S. nuclear weapons.

“The national security argument is ridiculous,” said Edwin Lyman, a nuclear proliferation expert at the Union of Concerned Scientists. “Ill-advised policies such as bolstering the floundering nuclear industry by declaring it a national security asset is just taking us in the wrong direction as far as having a sensible energy policy.”

The United States would also be undercutting the argument it uses with countries such as Iran and Saudi Arabia that want to control their own nuclear fuel cycles, Lyman said.

The two uranium mining companies said some needs could be as little as 10 years away. “I know it sounds like a long time but these projects can take decades, at least 10 years to get up and running,” John Cash, vice president regulatory affairs at Ur-Energy, said in an interview.

He and Paul Goranson, chief operating officer of Energy Fuels, said there are restrictions on the military use of uranium from foreign companies even if they are located in the United States. Both Ur-Energy and Energy Fuels are the sole parts of holding companies in Canada, but their operations, more than half their boards and all their employees are in the United States.

Industry analysts note that uranium prices are very low because of low demand. Ever since the Fukushima earthquake, Japanese nuclear plants have been largely idle. Germany closed several plants and plans to close the rest. The U.S. nuclear fleet, the world’s largest, is aging and having trouble competing with natural gas. Earlier, as part of the Megatons to Megawatts program, the United States imported highly enriched uranium from deactivated Russian weapons and downblended them for use in U.S. commercial reactors.

Utilities have benefited from the low demand and low prices. The Nuclear Energy Institute also said it was opposed to any moves to limit imports. “We sympathize with the plight of uranium suppliers,” NEI President Maria Korsnick said in a statement. “However, NEI does not support the implementation of quotas as described in the petition. Potential remedies could put even more generating units at risk for premature closure, which would further soften the market for uranium.”

Recently, uranium mining companies worldwide have been closing operations. The Canadian firm Cameco shut its McArthur River Mine and Kazakhstan’s Kazatomprom announced that it would cut output. Energy Fuels and Ur-Energy said in a statement that U.S. production this year would drop by nearly half.

Such cutbacks have “been the defining — and frustrating — characteristic of the uranium market over the past few years,” Energy Fuels CEO Mark Chalmers told shareholders in a letter earlier this year, according to an investor publication StreetWise Reports. While Chalmers said production cuts would boost prices, “the recovery has thus far eluded us.”

In much of the world, uranium mining is done by state-owned companies better able to weather a period of losses.

Some backers of U.S. uranium mining praised Ross’s investigation. Sen. John Barrasso (R-Wyo.), whose home state has uranium deposits, applauded Ross and said “For years, Russia, Kazakhstan, and Uzbekistan have undermined America’s uranium producers. We shouldn’t rely on foreign regimes to supply America with uranium.”

Energy Fuels has been active in Washington. In a separate lobbying campaign, the company sought to scale back Bears Ears National Monument, saying such action would give it easier access to the area’s uranium deposits and help it operate a nearby processing mill, according to documents obtained by The Washington Post.

The company hired a team of lobbyists at Faegre Baker Daniels — earlier led by Andrew Wheeler, who is now acting administrator of the Environmental Protection Agency.

Interior Secretary Ryan Zinke and top Utah Republicans have said repeatedly questions of mining or drilling played no role in President Trump’s announcement that he was cutting the site by more than 1.1 million acres, or 85 percent.

Ross on Wednesday said he had sent a letter to Defense Secretary Jim Mattis, informing him of the investigation. Ross has up to 270 days to make recommendations to President Trump, who would have 90 more days to act on the secretary’s recommendation.

Correction: An earlier version of this story misspelled the last name of the chief operating officer of Energy Fuels. He is Paul Goranson, not Garonson. The article has been updated.