A federal appeals court ordered the Trump administration to halt construction on its White House ballroom, saying the project needs approval from Congress in order to continue.

“Whether or not a massive ballroom should be constructed is for Congress to decide and is not a matter for Executive self-help,” the U.S. Court of Appeals for the D.C. Circuit wrote in a 136-page ruling issued Friday.

The three-judge panel issued a 2-1 ruling, but it says it will stay its order for two weeks to allow the Trump administration to appeal to the Supreme Court.

NPR has reached out to the White House for comment but did not hear back in time for publication.

President Trump slammed the decision within two hours, calling it “horrendous, politically motivated and unlawful.” He wrote on Truth Social that his administration will appeal immediately. He pointed out that the two judges who sided against him in the ruling were appointed by Democratic presidents: Barack Obama and Joe Biden.

Trump also repeated his administration’s argument that the ballroom is a matter of national security, and that Friday’s ruling threatens it.

The decision “severely jeopardizes the lives and welfare of the people who work, and will be working, at the White House — including all future Presidents of the United States, and their families, as well as the lives of all those visiting, such as Heads of State and other Dignitaries, and all Americans who wish to visit the historic, beautiful Executive Mansion,” Trump wrote.

The nonprofit National Trust for Historic Preservation, chartered by Congress, which brought the lawsuit late last year, celebrated the ruling.

“This is a great day for our country and for the American people’s right to voice their opinions about the historic places they cherish, including the White House,” Brent Leggs, its president and CEO, said in a statement shared with NPR.

Friday’s ruling is the latest chapter in a saga that began in October, when the Trump administration started demolishing the East Wing of the White House to make way for Trump’s long-held dream of a presidential ballroom.

The administration has said the ballroom will total roughly 90,000 square feet and seat 1,000 guests. The White House originally estimated the cost at $200 million, but the Washington Post reported in June — citing contractors’ invoices — that the total cost could be at least $600 million.

Rep. Andy Ogles of Tennessee has lost his Republican primary, NBC News projects, falling to a former state official in a primary season that has seen an unusually high number of incumbents lose renomination.

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Charlie Hatcher, the former state agricultural commissioner, rode support from prominent establishment Republicans to a victory over Ogles, a controversial congressman backed by President Donald Trump. He is a heavy favorite in the general election in the deep-red district.

Ogles was outraised and outspent on the airwaves, largely because of a massive ad effort from a pro-clean energy group — a last-minute campaign Ogles criticized in an interview with Fox News.

While Ogles had arguably the most important endorsement in a GOP primary in Trump’s, Hatcher had backing from Gov. Bill Lee, former Gov. Bill Haslam and other prominent Republicans, like former Trump Agriculture Secretary Sonny Perdue.

Ogles has faced various controversies over the years. He said this year that Muslims don’t belong in American society, deleted a homophobic social media post after having blamed a staffer and argued last year that the federal government should revoke future New York Mayor Zohran Mamdani’s citizenship and deport him.

He was also investigated on suspicion of campaign finance violations; he has not been charged with any crimes. Ogles told The Associated Press that the Justice Department returned his cellphone, which it had seized during the investigation.

But while Ogles had fended off a well-funded primary opponent before, he couldn’t do it this time. Hatcher didn’t run away from Trump, either, despite Trump’s support for Ogles. Hatcher aligned himself with Trump and his policies and sought to contrast himself with Ogles.

“Think what President Trump could do if our congressman spent less time talking and more time doing,” reads a quote on Hatcher’s website.

Ogles is the ninth House member — six Democrats and three Republicans — to lose a primary this year. That’s the most in a nondecennial redistricting year since 1970, according to Vital Statistics on Congress.

Two senators, Republicans Bill Cassidy of Louisiana and John Cornyn of Texas, also lost their primaries, and an additional House member — Rep. Tony Gonzales, R-Texas — finished second in his primary and then decided to drop out of the race and resign before a GOP runoff.