An American appellate court has ordered an immediate halt to a $400 million ballroom construction project at the White House, ruling that Congress approval is required for such major alterations to the historic residence.

A three-judge panel at the US Court of Appeals for the District of Columbia has issued a directive to stop work on President Donald Trump's planned ballroom at the White House, marking a significant legal setback for the administration. The court ruled by a 2-1 majority that decisions regarding construction of this magnitude fall under congressional authority rather than executive power.

The judges emphasized that while each president serves as a temporary resident of the White House, they do not own the building and cannot unilaterally modify a historically significant structure according to personal preferences. The court stated that the building was designed for current and future presidents as well as the American people, and major changes require legislative approval rather than presidential discretion alone.

The Trump administration had previously demolished the historic East Wing of the White House without congressional authorization to make way for the ballroom project. This action prompted the National Trust for Historic Preservation to file a legal challenge. While a lower court had imposed a temporary injunction on above-ground construction work, the government appealed that decision, which the appellate court has now upheld.

The appellate court has granted a 14-day period before the ruling takes effect, allowing the administration an opportunity to appeal to the US Supreme Court. No construction work may proceed until congressional approval is obtained, according to the court's determination.