A divided federal appeals court ruled Friday that the Trump administration must halt construction of a massive 400 million dollar ballroom at the White House, determining that the president cannot unilaterally move forward with such a project without explicit approval from Congress. The decision by a three judge panel from the U.S. Court of Appeals for the District of Columbia Circuit comes after historic preservationists sued to stop the development of the 90,000 square foot structure, which replaced the former East Wing. While the court granted a two week stay to allow for an appeal, the judges emphasized that deciding whether to build such a facility is a legislative matter rather than one of executive self help.

President Trump quickly blasted the ruling on social media, calling it unjust and politically motivated while vowing to take the fight to the Supreme Court. To justify the scale of the project, the president noted that the complex is intended to house critical infrastructure including bomb shelters, medical facilities and top secret military installations designed for national security and the protection of future presidents. He previously argued that congressional permission was unnecessary because he claimed much of the funding came from private donations and his own wealth, though critics point out that his administration had previously requested a billion dollars in public funds for the project which Congress rejected in May.

The legal victory was celebrated by the National Trust for Historic Preservation, whose leadership stated that the ruling affirms the rights of American citizens to protect cherished historic landmarks. This latest judicial setback follows another controversy regarding a proposed 250 foot tall triumphal arch near Arlington National Cemetery, which experts warn could damage several nearby historical sites. For now, while underground work on bunkers and security facilities remains permitted under previous orders, any further above ground progress on the grand ballroom depends entirely on either a reversal from the high court or an act of Congress.