A New York state appeals court judge has temporarily halted the scheduled trial in New York Attorney-General Letitia James’ fraud lawsuit against Donald Trump and his family business.

The order came on Thursday after the former US president sued Justice Arthur Engoron, the trial judge overseeing the case, accusing him and James of defying a court order that could narrow the lawsuit, according to a report in the Daily Beast.

According to the court spokesman, appeals court Justice David Friedman granted an interim stay of the trial, and referred the matter to a five-judge panel, which expects to rule in the last week of September.

The trial could still begin on October 2 depending on how the appeals court, known as the First Department, rules.

Friedman’s stay does not apply to a scheduled September 22 hearing before Engoron on both sides’ motions for summary judgment, which can proceed as planned, the court spokesman said.

James wants a ruling that Trump’s financial statements were fraudulent, while the defendants want most or all of the attorney-general’s claims dismissed. Engoron has said the trial could last until near Christmas.

Lawyers for Trump did not immediately respond to requests for comment. James’ office did not immediately respond to similar requests.

James has said a “mountain of evidence” shows how Trump and his associates lied over a decade about his assets and net worth, which she says may have been inflated by as much as $US3.6 billion ($A5.6 billion), to obtain better terms on loans and insurance.

She is seeking a $US250 million ($A389 million) fine, and to bar Trump and his sons Donald Trump Jr and Eric Trump from leading the family business, the Trump Organisation. Her lawsuit in September 2022, after a three-year probe.

In July, the appeals court said statutes of limitations may preclude James from suing over claims that arose before July 13, 2014, or February 6, 2016, and said Engoron should decide which could proceed.

Trump holds a dominant lead in the 2024 race for the Republican presidential nomination.

He has denied wrongdoing, and called James’ case part of a Democratic “witch hunt”.

In January, Engoron said the “witch hunt” argument did not justify a dismissal, and said some defence arguments were “borderline frivolous even the first time defendants made them.”