Washington DC - A US federal judge ruled on Monday to halt tree-cutting at a public golf course in the heart of the capital, after hundreds of trees were felled in Donald Trump's pet project.

The president has called for Washington's East Potomac Golf Links, a public course with affordable rates, to be remodeled into a facility capable of hosting major championship-caliber events.

The early demolition for the overhaul had charged ahead despite an environmental group's lawsuit, and opposition from local golfers who argue the 100-year-old course is a rare spot where they can affordably play the sport.

"The Court ENJOINS defendants from removing or damaging additional trees on East Potomac Golf Course and ORDERS them to provide ten business days' written advance notice before making any irreparable modification to any forms or features of East Potomac Park, pending the outcome of this litigation," District Judge Ana Reyes wrote in Monday's 70-page order.

"The Government felled hundreds of trees from the East Potomac Golf Course without real notice even though it knew of the scheduled removal at least a week prior," Reyes said, adding they were "healthy, nonhazardous trees."

Trump said this month that construction was set to start in November on the 18-hole course. He insisted on Monday that the site would close for renovation as scheduled on November 15 and pledged to appeal Reyes' decision.

"The judge has absolutely no right to hold up this very important and beautiful Project," Trump wrote on Truth Social.

More than 500 trees have already been cut down, the judge wrote.

The court "does not speak for the trees," Reyes wrote in her order, in reference to the Dr. Seuss book The Lorax. "It speaks only for the rule of law."