WASHINGTON, D.C. — President Donald Trump showed reporters design renditions of a new White House ballroom aboard Air Force One on Sunday and revealed that the military is constructing a "massive" underground complex beneath the facility currently under construction.

"The information has come out recently because of a stupid lawsuit that was filed, but the military is building a massive complex under the ballroom, and that's under construction, and we're doing very well," Trump said. "So we're ahead of schedule."

The East Wing of the White House was demolished in October to make way for the $400 million, 90,000 square foot ballroom. Plans call for renovation of a military bunker under the East Wing.

A federal judge rejected a lawsuit from a preservationist group that sought to stop the Trump administration from continuing construction of the ballroom. The judge said that the National Trust for Historic Preservation would have a better chance of winning the claim if the group changed their arguments in the lawsuit, according to court filings.

Trump explained his decision to discuss the project with reporters on Sunday, saying he was balancing the disclosure with other presidential duties. "I thought I'd do this now because it's easier. I'm so busy that I don't have time to do this, but I'm fighting wars and other things."

The president expressed confidence in the ballroom's future significance, calling it "very important, because this is going to be with us for a long time, and it's going to be, I think it'll be the greatest ballroom anywhere in the world."

The National Capital Planning Commission is scheduled to vote on the ballroom plans in April.