3/3Reuters. U.S. President Joe Biden delivers remarks after touring Ford Rouge Electric Vehicle Center in Dearborn, Michigan, U.S., May 18, 2021. /Leah Millis2/3By Ernest Scheyder Lithium Americas (NYSE:LAC) Corp has delayed plans to excavate its Thacker Pass lithium mine site in Nevada, according to court filings, while a federal judge considers whether the former Trump administration erred in approving the project that opponents say could threaten sage grouse and other wildlife. The delay is the latest setback for the U.S. critical minerals industry as environmentalists pressure courts and regulators to block mining projects from a slew of companies including ioneer Ltd , Antofagasta (LON:ANTO) Plc , Rio Tinto (NYSE:RIO) and others, even if those mines produce metals key to fighting climate change. Thacker Pass, if completed, would be the largest lithium mine in the United States, producing 30,000 tonnes of lithium annuallyenough to make more than 475,000 electric vehicle (EV) batteries. The court case, though, is likely to push back the company's development timeline and an adverse ruling could seriously imperil it. Mine opponents have asked a federal judge to rule by next month on whether Vancouver-based Lithium Americas may dig at the northern Nevada site. The company had intended to start digging at the site on June 23, several months earlier than initially planned. Opponents requested a temporary injunction to block excavation while the court considers the broader case, which centers on whether the U.S. Bureau of Land Management (BLM) erred in approving the project in January less than a week before U.S. President Donald Trump left office. Thacker Pass has been under review for more than a decade. Lithium Americas this week agreed to pause digging through late July, according to filings. SAGE GROUSE Environmentalists filed the suit after that BLM decision, arguing in part that regulators did not abide by federal statues designed to protect sage grouse. The company and BLM disagree, according to filings. "These sage grouse protections are the law of the land and we feel we have a strong case with our injunction motion," Roger Flynn, an attorney representing conservation groups, told . Chief Judge Miranda Du of the federal court in Reno, who is overseeing the case, has in the past ruled in favor of preserving sage grouse habitats. If Du grants the injunction, Lithium Americas would not be able to develop the site while she considers the broader question of whether the Trump administration erred in approving the mine. A ruling on that is expected later this year or in 2022. In a statement, Lithium Americas said it is "confident the BLM's extensive and approved environmental impact statement will withstand judicial scrutiny." Lithium Americas told the court that blocking the mine would harm national security and impede President Joe Biden's plan to wean the U.S. economy off fossil fuels. reported last month that Biden plans to look abroad for most supplies of EV metals, part of a strategy designed to placate environmentalists. Lithium Americas has an unlikely ally in Glenn Miller, who founded the environmental group Great Basin Resource Watch, which is one of the conservationist groups suing to block the mine. Miller said he disagrees with the group's opposition to the project and resigned from its board earlier this week. "Everyone is deeply concerned about climate change. It's a question about values, and I go with the need for lithium," said Miller, a retired professor at the University of Nevada. "This is one of the least-impactive mine plans I've ever seen."