A ruling in the New York state attorney-general’s multimillion-dollar civil fraud case against former US president Donald Trump has been delayed.

Justice Arthur Engoron, who oversaw a three-month trial in the $US370 million ($568 million) case last year, had said he planned to rule by the end of January but offered no guarantees.

His eventual ruling could deal a major blow to Trump’s business empire as the businessman-turned-politician seeks the Republican nomination to challenge Democratic President Joe Biden in the November US election.

The lawsuit brought by New York Attorney-General Letitia James accused Trump and his family businesses of overstating his net worth by as much $US3.6 billion ($5.5 billion) a year over a decade to secure better loan terms.

Trump has denied wrongdoing and called the case a political vendetta by James, an elected Democrat.

In addition to monetary penalties, James is seeking to permanently ban Trump from New York’s real estate industry and sharply limit his ability to do business in the state.

Engoron previously ruled in September that Trump had engaged in fraud and ordered his business empire be partially dissolved. The full implications of that order are still unclear, and Trump is appealing.

Closing arguments were delivered in the case on January 11, with Engoron saying on that day he had hoped to issue a ruling by January 31.

On Thursday (US time), a court spokesperson said the ruling was now likely by “early to mid-February”. But they cautioned it was a “rough estimate” and was “subject to modifications”.

On the day of closing arguments, Trump lashed out at the judge in the courtroom, telling him, “You have your own agenda. I understand that you can’t listen for more than one minute.”

“Please control your client,” the judge told Trump’s lawyer, Christopher Kise.

– with AAP