NEW YORK — On his second day of testimony, fireworks erupted between Donald Trump's former personal attorney, Michel Cohen, and his current legal defense team in a high-stakes fraud trial.

The heated day featured multiple procedural skirmishes between the defense attorneys, prosecutors, and Judge Arthur Engoron, culminating in a $10,000 (£8,250) fine against Trump for violating a gag order against speaking or posting about court staff.

Earlier in the day, Trump had told reporters that Engoron was a "very partisan judge, with a person who is very partisan sitting alongside him, perhaps even much more partisan than he is". His comments followed a previous social media attack against the judge's clerk earlier this month, which had led to the gag order and a fine.

In a dramatic moment shortly after 2 pm, the judge forced Trump to briefly take the stand to settle the matter.

When questioned on the stand, Trump told the judge he was referring to "You and Cohen", not the judge and his clerk.

Yet Judge Engoron found his explanation "not credible," and fined him $10,000 for a repeated violation of the gag order.

"I am very protective of my staff as I believe I should be," Judge Engoron had said earlier in the day, citing the "heated environment" around the case. "I don't want anybody to get killed."

It was the capstone of a long and rocky day in court starring Trump's former personal counsel.

Cohen is a key witness in a case brought by New York attorney general Letitia James, which alleges that the Trump Organization and its top figures fraudulently inflated the value of its assets to secure more favourable loans.

Judge Engoron has already ruled the organisation committed fraud, and the current trial is focused on additional charges. There is no jury, and an unfavourable ruling could put Trump's New York real estate empire in peril.

On Wednesday, Trump's team was clearly taking the offensive.

Through a steady staccato of questions, attorney Alina Habba sought to undermine Cohen's credibility and question his motivations.

"You have made a career out of publicly attacking President Trump haven't you?" she said in one instance.

Cohen admitted he had.

"The more outrageous your stories are about President Trump, the more money you make?" she asked later.

Cohen responded "no".

At one point, he grew frustrated with Ms Habba's questions. "I answered every question that you want, why are you screaming at me?" he blurted.

Meanwhile, Trump, not typically one for verbal restraint, sat quietly and let his lawyers do the fighting for him.

Once Trump's trusted personal lawyer, Cohen went to great, and at some points illegal, ends to obtain a favorable outcome for him.

His association with Trump drew him into legal peril in 2018, when he pleaded guilty to charges of tax evasion, lying to a bank, and campaign finance violations. He spent just over a year behind bars and has since become one of Trump's fiercest critics.

Now he is a star witness in not one but two cases against Trump — this investigation into his businesses, and another investigation by the Manhattan District Attorney into hush money payments made to an adult film star with whom Trump allegedly had affair. Trump denies wrongdoing in both cases, as well as the affair.

This week is the first time the two have met face to face in years.

During his testimony, Cohen told prosecutors that Trump had personally directed him and the convicted ex-chief financial officer of the company to "arbitrarily" inflate the value of assets in order to reach a desired number.

But during cross-examination, Trump's defense lawyers sought to undermine his character by accusing Cohen of perjury.

On Tuesday, Cohen had said he was not being truthful when he pleaded guilty to charges of tax evasion in a separate 2018 case; he did not believe he had committed that crime.

Then on Wednesday, Trumps' lead attorney, Chris Kise, declared that Cohen "admitted here today in open court that he lied".

Prosecutor Colleen Faherty interjected, and asked for respect without this "showmanship".

Kise responded that "there is nothing wrong with calling a liar, a liar".

Eventually Judge Engoron asked them to move on.

Toward the end of the day, another of Trump's attorneys made a Hail Mary request to the judge to end the trial, citing the credibility of Cohen's testimony.

"Absolutely denied," Judge Engoron said. "No way, no how." — BBC