RENO, Nev. (AP) — A federal appeals court has cleared the way for construction in Nevada of the largest lithium mine in the U.S. while it considers claims by conservationists and tribes that the government illegally approved it in a rush to produce raw materials for electric vehicle batteries.

The 9th U.S. Circuit Court of Appeals on Wednesday denied request for an emergency injunction that would have prevented a subsidiary of Lithium Americas from breaking ground near the Oregon line this week at the third largest known lithium deposit in the world.

Lawyers for the mining company and the Biden administration said in court filings on Tuesday further delay was undermining efforts to combat climate change as the 2-year-old legal battle lingers and demand continues to grow for the key component in batteries for electric vehicles.

Reserves at the Thacker Pass mine, expected to begin production by the end of 2026 about 200 miles northeast of Reno, would support lithium for more than 1.5 million electric vehicles per year for 40 years, the company said.

“There are no other U.S. alternatives to Thacker Pass to provide lithium at the scale, grade or timeline necessary to begin closing the gap between the lithium available and the lithium needed to achieve the U.S.’s clean energy and transportation goals,” its lawyers wrote.

But another announcement on Wednesday cited the discovery of one of the largest known lithium deposits in the country.

American Battery Technology Company, a Reno company formed by a former Tesla research and development executive, reports that lithium deposits at Tonopah Flats in Big Smoky Valley are estimated to contain 15.8 million tons of lithium carbonate equivalent.

That site isn’t far from Rhyolite Ridge, a venture by Australian mining company Ioneer that has been slowed by environmentalists’ claims that the area is the habitat of a rare plant known as Tiehm’s buckwheat.

On Wednesday, the San Francisco-based court scheduled expedited filing deadlines through April on the merits of the appeal but its four-page ruling didn’t explain its rejection of the injunction.

Environmentalists and tribes trying to block the project support efforts to bolster lithium supplies to build electric vehicle batteries and replace fossil fuels with renewables but they say this particular mine would destroy essential wildlife habitat and sacred cultural values.

Opponents of Lithium Nevada Corp.’s project filed an emergency motion with the 9th Circuit on Monday after U.S. District Judge Miranda Du in Reno rejected their latest request to put the case on hold until the San Francisco-based appellate court can hear their appeal.

Du ruled on Feb. 6 the Interior Department’s Bureau of Land Management complied with federal law — with one exception — when it approved plans for the mine in January 2021. On Friday, she refused the request for an injunction pending appeal.

Judge Du “reasonably weighed the public interest and balance of harms, noting that the lithium from this mine is a critical component of electric vehicle batteries, and thus an important domestic resource for reducing greenhouse gas emissions,” Biden administration officials representing BLM said in court filings Tuesday.

Billions of dollars in investments are at stake in the legal battle at the forefront of so-called green energy development in the largest gold-producing state in the nation.

Neighboring California — the nation’s largest car market — plans to end the sale of new gas cars and trucks in a little over a decade, which will further drive up demand for electric vehicle batteries.

A Nevada rancher filed the first lawsuit in early 2021 seeking to block the 5,000-acre project with an open-pit mine as deep as a football field.

Multiple Native American tribes have tried unsuccessfully to persuade Judge Du that the development will destroy sacred cultural values tied to the nearby site of a massacre of dozens of their ancestors in 1865.

A half-dozen conservation groups say habitat critical to dwindling sage grouse, pronghorn antelope, threatened cutthroat trout and others could be lost forever as a result of the project. The groups say the Bureau of Land Management rushed without adequate environmental review in the final days of former President Donald Trump’s administration.

“Together, these voices paint a powerful picture of the values at stake from the project that (Lithium Nevada) is now trying to greenwash,” the opponents’ lawyers wrote in court briefs late Thursday.