A US Federal Appeals Court has ordered the administration of President Donald Trump to stop construction of a $400 million ballroom on the site of the demolished East Wing of the White House, dealing a major setback to the Republican president in a case testing the limits of executive authority.
The US Court of Appeals for the District of Columbia Circuit ruled 2-1 that the administration could not proceed with the project without approval from Congress.
"Each President is a temporary tenant, not the owner, of the White House," the court said, ruling that the President cannot fundamentally reshape the complex without congressional authorisation.
The ruling upheld a preliminary injunction obtained by the National Trust for Historic Preservation, which sued after the administration demolished the East Wing and began work on a planned 90,000-square-foot (8,360-square-metre) ballroom without seeking congressional approval.
"Whether or not a massive ballroom should be constructed is for Congress to decide and is not a matter for Executive self-help," the majority said.
The appeals court has stayed its ruling for 14 days, allowing the Trump administration time to appeal to the US Supreme Court.
Trump said he would challenge the decision, describing it as "horrendous" and politically motivated.
In a post on Truth Social, he referred to the proposed structure as a "military center" and argued that its security features were necessary to protect the President, White House officials and visitors from potential attacks.
"This unjust decision must be overturned by the Supreme Court in its entirety," Reuters cited Trump writing.
He said the ballroom would incorporate bomb shelters, medical facilities and protection against drones and missiles, describing the security measures as "all tied together as one big, expensive, and very complex unit."
National Trust for Historic Preservation president Brent Leggs welcomed the ruling, calling it "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."
Trump had appealed after US District Judge Richard Leon, an appointee of former Republican president George W. Bush, twice blocked above-ground construction at the site while allowing underground work to continue.
The ballroom, which the administration has described as necessary for large formal functions and to improve White House security, is among the most ambitious of Trump's efforts to reshape Washington's government buildings and national monuments.
At arguments before the appeals court in June, Justice Department lawyer Yaakov Roth argued that the courts had no role in determining whether the privately funded project should proceed.
He said the National Trust's "architectural preference" should not override national security considerations, citing evidence that the former East Wing had left the President and others in the White House vulnerable to attack.
However, Circuit Judges Patricia Millett and Brad Garcia, both appointed by Democratic presidents, said their ruling did not permanently prevent construction of a ballroom.
Instead, they said above-ground work would remain halted while the legal challenge continued and until the White House obtained congressional approval.
"National security arguments are not an automatic get-out-of-law-free card," the majority said.
"The bold assertion that the Executive can act with utter lawlessness, destroying treasured national landmarks and harming the interests of individuals, and that no court can stop it flouts our constitutional order," the judges wrote.
Circuit Judge Neomi Rao, whom Trump appointed during his first term, dissented, saying the injunction blocking construction exceeded the proper role of the federal courts.
"The district court seized supervision of construction at the White House, and my colleagues affirm this judicial overreach," Rao wrote.
Trump has also defended the project's rising cost, which has doubled from its initial projections.
In May, he said the higher price reflected the ballroom being approximately twice the size and of a much higher quality than originally proposed, while promising that it would be "magnificent, safe, and secure!" - August 8, 2026