Former US President Donald Trump attends his trial for allegedly covering up hush money payments linked to extramarital affairs, at Manhattan Criminal Court in New York City, on May 2, 2024. [AFP]

Prosecutors accused Donald Trump on Thursday of "willfully and knowingly" violating a gag order imposed by the New York judge overseeing his hush-money case to protect trial participants.

Trump, 77, is accused of falsifying business records to reimburse his lawyer, Michael Cohen, for a $130,000 payment made to porn star Stormy Daniels just days ahead of the 2016 election against Hillary Clinton.

Judge Juan Merchan has already sanctioned the property mogul for defying his gag order on nine occasions, fining him $9,000 on Tuesday and warning Trump he could face jail for continuing to lash out on social media.

Prosecutor Christopher Conroy urged the judge at Thursday's contempt hearing to fine Trump the maximum of $1,000 for each of four new violations of the gag order barring him from publicly attacking witnesses, jurors, court staff, or their relatives.

"We are not yet seeking jail," Conroy said.

"The defendant willfully and knowingly violated the order," Conroy said. "The defendant thinks the rules should be different for him.

"The defendant has proven his willingness to say and do anything to disrupt this process."

Conroy pointed to public comments Trump has made about Cohen, his former "fixer" turned foe, and the composition of the jury as violations of the gag order.

Todd Blanche, Trump's attorney, noted that Trump is the Republican candidate for president and said his likely November election rival, Democrat Joe Biden, had spoken publicly about the trial.

"He can't respond," Blanche said.

The judge said that was not true and there was nothing in the gag order that limits what Trump can say in response to Biden.

The judge also took issue with Trump's claim he cannot get a fair trial in New York because it is a heavily Democratic city.

"He spoke about the jury... and that it was 90 percent Democrat," Merchan said. "The implication being this is not a fair jury."

No-nonsense judge

On Wednesday, Trump took advantage of a break in the trial to hold campaign rallies in Wisconsin and Michigan -- blaming his legal troubles and America's ills on Biden.

Before going into court on Thursday, he denounced his trial as "election interference" and said the case "should never have been brought."

Trump regularly claims that his indictments -- three for alleged cheating in elections and one for hoarding classified documents after leaving the White House -- are being orchestrated as part of a political "witch hunt," but never offers any evidence.

The court has heard from an eclectic slate of witnesses including a lawyer, Keith Davidson, who helped negotiate the hush money payment to Daniels just days ahead of the 2016 election.

Davidson returned to the witness stand on Thursday after the hearing about the gag order violations. Merchan did not issue an immediate ruling on the alleged violations.

Trump is the first former US president to face criminal charges, and the trial in a chilly Manhattan courtroom has him frustrated.

For two weeks Trump has sat through hours of sometimes technical testimony, visibly irate with the no-nonsense judge, who has required him to be present every day.

Before and after each day's proceedings, Trump has assailed journalists outside, venting about his legal problems and myriad other issues.