A federal appeals court on Friday ordered the Trump administration to halt construction of its White House ballroom, ruling that the project requires authorization from Congress to proceed.

The U.S. Court of Appeals for the D.C. Circuit issued the 136-page opinion on Aug. 7, 2026. A three-judge panel ruled 2-1 against the administration and said it would pause its order for two weeks to allow an appeal to the U.S. Supreme Court, NPR reported. The ruling and its accompanying pause were documented in the court's published opinion.

The lawsuit was brought by the National Trust for Historic Preservation, a nonprofit chartered by Congress. The organization sued the administration in December 2025 seeking to halt the project until the legally mandated review process, including obtaining congressional approval, was completed. The challenge targeted President Donald Trump's authority to demolish the White House East Wing without legislative authorization.

President Trump called the appeals court decision "horrendous, politically motivated and unlawful" and said his administration would appeal immediately. He noted that the two judges in the majority were appointed by Democratic presidents Barack Obama and Joe Biden.

The administration had argued the ballroom is a matter of national security. In the lawsuit, the administration also argued that the plaintiffs lacked legal standing — the right to sue because of a direct connection to the harm at issue — to challenge the construction.

The White House announced plans to build a roughly 90,000-square-foot ballroom at the site of the East Wing on July 31, 2025. The planned ballroom, to be built in President's Park using privately donated funds, is expected to seat 1,000 guests. Demolition of the East Wing began in October 2025 to make way for the new construction.

Cost estimates for the project have varied. The White House originally estimated the ballroom's cost at $200 million. The Washington Post reported in June 2026 that the total cost could reach at least $600 million. An April 2026 report in The Daily Record placed the project's cost at $400 million.

The National Trust for Historic Preservation initially sued to halt construction in December 2025. On April 11, 2026, a three-judge D.C. Circuit panel ruled 2-1 that construction could continue temporarily while the lower court ruling was reviewed, extending a freeze until April 17, 2026. The Guardian reported on April 18, 2026 that the administration was cleared to continue construction after the project had been stopped.

At a June 5, 2026 hearing, the D.C. Circuit appeals court panel sharply questioned the administration's authority to build the ballroom without congressional authorization. Reuters reported at the time that the appeals court could rule within weeks in the preservationists' challenge.

SCOTUSblog reported in June 2026 that the White House ballroom dispute may soon arrive at the Supreme Court. With the D.C. Circuit's Friday ruling and its built-in two-week pause, the administration now has a direct path to escalate the matter to the high court.

Brent Leggs, president and CEO of the National Trust for Historic Preservation, celebrated the appeals court ruling.

The broader context here is a separation-of-powers dispute over the executive branch's authority to unilaterally alter a historically protected federal site. The administration's argument that the ballroom constitutes a national security facility, combined with the use of private donations, tests the boundaries of congressional oversight over modifications to the White House grounds and President's Park. The D.C. Circuit's 136-page opinion concludes that these justifications do not bypass the requirement for legislative approval, setting up a Supreme Court review on whether the executive can proceed with major alterations to the complex without congressional authorization.