Washington DC: A Washington-based nonprofit organisation, the National Trust for Historic Preservation, has filed a lawsuit to stop the Trump administration’s construction of a large new ballroom connected to the White House’s east wing, Al Jazeera reported.

According to Al Jazeera, the legal challenge—filed on Friday—targets one of US President Donald Trump’s major renovation projects, a proposed 90,000-square-foot expansion to the White House complex.

Preservationists have long criticised the project, arguing that it alters the historic character of the White House and that the administration failed to follow proper review procedures. This marks the first formal legal effort to halt the construction.

Calling the White House “one of the most significant symbols of American ideals,” National Trust President Carol Quillen said the organisation felt obligated to intervene. “As the group responsible for safeguarding places where our history unfolded, the National Trust was compelled to file this case,” she said, as quoted by Al Jazeera.

The lawsuit alleges multiple violations, including the administration’s failure to submit construction plans to the National Capital Planning Commission, the lack of an environmental assessment, and failure to obtain congressional approval for construction within a federal park.

It further argues that the administration’s actions violate the US Constitution’s property clause, which grants Congress authority over federal property, Al Jazeera reported.

The Trust had earlier called for a pause in construction through letters to the National Capital Planning Commission, the National Park Service, and the Commission of Fine Arts.

While the Trump administration has not responded to the lawsuit, officials have maintained that the project complies with the law, according to Al Jazeera.

In October, Trump aide and White House Communications Director Steven Cheung dismissed the National Trust as being “run by a bunch of loser Democrats and liberal donors playing political games.”

President Trump, who has a background in real estate, is a strong proponent of the ballroom project. Demolition work on part of the east wing began in October.