Washington DC - The Supreme Court on Monday allowed President Donald Trump to continue construction of his White House ballroom, granting him a major victory in a lawsuit over a key project of his second term.

The conservative-dominated court voted 5-4 to lift a lower order demanding construction be halted, with Chief Justice John Roberts notably joining the court's three liberals in dissenting.

Roberts earlier this month issued a temporary order to allow construction while the full court weighed the matter.

The project has roiled Washington, with critics saying Trump acted unlawfully by unilaterally ordering the demolition of the entire White House East Wing.

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The court decision means construction will advance, while a lawsuit brought by the National Trust for Historic Preservation will play out in lower courts – a process that could take months or years.

The National Trust did not immediately return AFP's request for comment.

In its decision, the court said that the government was likely to eventually win the ongoing lawsuit because the National Trust probably did not have the right to bring the claim in the first place.

The organization's case is grounded by one of its members, Washington resident Alison Hoagland, who claims that seeing the finished ballroom would result in damage to her "aesthetic, cultural, and historical interests," due to its size.

"This Court has not found standing in circumstances like these before. To the contrary, we have repeatedly held that mere offense, disagreement, or distaste does not qualify as a concrete and particularized injury," under the US Constitution, the five justices wrote in their ruling.

"Perhaps nearly any government action or project offends someone's sensibilities," they added.

However, those justices made clear that they were not making a final ruling on the legality of the ballroom project, just that construction could continue while the case is argued and decided in lower courts.

The dissenting justices wrote that the project was "likely unlawful," because "Congress has not passed any law resembling 'express authority'" for the administration to undertake it – despite a law requiring it to do so.

They also argued that Hoagland's claim "suffices for standing."

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While the ballroom has drawn headlines, the project also includes a military bunker.

A district court and, later, an appellate court, halted work on the ballroom while allowing construction on the military facility to continue.

The president has trumpeted the ballroom as necessary for hosting galas and state dinners, while also stressing the national security need for the bunker.