MADISON, Wis. — A federal appellate panel on Monday dismissed state officials’ efforts to obtain federal funding to expand a highway between Fond du Lac and Sheboygan.

Wisconsin officials have been trying to secure federal funding to widen a 19-mile stretch of State Highway 23. A February 2017 state Department of Transportation report put the cost at between $150 million and $158 million.

A group called 1,000 Friends of Wisconsin that works for sustainable, environmentally friendly land use filed a lawsuit in 2011 to stop the project. The group argued that a federal environmental impact statement was incomplete and without it the federal government can’t distribute any money.

U.S. District Judge Lynn Adelman sided with the organization in May 2015, vacating the U.S. Department of Transportation’s decision to pay for the project.

Wisconsin transportation officials appealed to the 7th U.S. Circuit Court of Appeals but the federal government did not. A three-judge panel from the appellate court ruled 2-1 on Monday that the federal decision not to appeal forecloses any other challenges. Judge Frank Easterbrook, writing for the majority, said Wisconsin can’t seek relief against a judgment that doesn’t bind it, noting the state can proceed with its own funds.

Dennis Grzezinski, 1,000 Friends of Wisconsin’s attorney, said he was pleased with the decision.

The state could appeal to the full 7th Circuit or the U.S. Supreme Court. State Department of Transportation spokeswoman Patricia Mayers said in an email that the agency is in the process of “developing the best option to move this project forward.” She didn’t elaborate.

Court filings from 1,000 Friends of Wisconsin put the cost of the project at $168 million as of February 2015. Mayers didn’t immediately respond to a follow-up email asking about the discrepancy between the group’s figure and the figures in the 2017 report.