The Trump Organisation has sued New York City for cancelling its contract to manage and operate a golf course in the Bronx earlier this year, a move it said was politically motivated and should be reversed.
The lawsuit, filed in state court today, says nothing in the 566-page contract gave New York City Mayor Bill de Blasio the right to terminate the deal after the president's supporters stormed the US Capitol earlier this year.
The company is demanding that it be allowed to continue to run the course, which has dramatic views of the Manhattan skyline, or that the city pay millions of dollars to buy it out.
The lawsuit is the opening shot in what is expected to be a protracted, and possibly costly, fight between the city and the Trump Organisation, according to several lawyers who reviewed the contract and experts familiar with the business practices of the litigious former US president.
"Mayor de Blasio's actions are purely politically motivated, have no legal merit, and are yet another example of the mayor's efforts to advance his own partisan agenda and interfere with free enterprise," the Trump Organisation said in a statement.
The city said Trump was clearly in breach of the contract terms and it will "vigorously defend" its decision.
When De Blasio announced he was kicking Trump off the course in January, he cited Trump's "criminal action" in inciting Capitol rioters, arguing that he could fire him "for cause" and not pay him a dime.
The firing was part of a backlash against Trump after the January 6 siege. Insurers, banks and brokers also refused to do any future business with the former president's company.
The city has also cited a decision by the PGA of America to cancel a tournament that was going to be held at one of Trump's golf courses in New Jersey.
The city said that Trump could no longer argue he can attract prestigious tournaments to the Bronx course, called Trump Golf Links at Ferry Point, as is required in the contract.
In its lawsuit, the Trump Organisation said the contract doesn't require it to attract tournaments, only obliging it maintain a course that is "first-class, tournament quality".
It attached letters from course designers, golf organisations and famous golfers - including top-ranked players Dustin Johnson and US Open champion Bryson DeChambeau - saying the course met that standard.
The city has previously argued that the Trump Organisation was being "overly restrictive" in its interpretation of the phrase "first-class, tournament quality", saying it need only show that Trump is incapable of attracting tournaments for whatever reason.
Under the terms of the contract, New York City can terminate its deal with Trump at any time without cause, but would be obligated to compensate his company for money it invested in building a clubhouse on the course.
Trump's son Eric, who lashed out at the city's decision as a part of "cancel culture" earlier this year, has said the city would have to pay more than US$30 million (NZ$42.9m), a figure cited again in the lawsuit.