Former President Donald Trump and New York Attorney General Letitia James, in separate media appearances, addressed the ruling Friday evening, trading barbs while reacting to the judgment.

Speaking from his Mar-a-Lago estate in Florida, Trump said he had to pay a fine for "having built a perfect company." Accusing both James and Judge Arthur Engoron of being politically motivated, Trump denied committing any fraud and said he plans to appeal.

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Trump responds to ruling: 'A crooked New State judge just ruled I need to pay a fine'

Meanwhile, in New York, James lauded the ruling as a victory for all Americans and the principles of equal justice under the law -- saying "former presidents are no exception."

"The scale and scope of Donald Trump's fraud is staggering -- and so, too, is his ego and his belief that the rules don't apply to him," she said.

James also heralded Judge Engoron's penalties as effective remedies to "ensure this fraud cannot continue."

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Letitia James delivers remarks after Trump ruling

Based on Friday's decision, former President Trump and his co-defendants will likely owe $463.9 million based on their initial fine and the prejudgment interest imposed by the court, according to a representative for the New York attorney general.

Trump himself will likely owe $453.5 million, between his $354.86 million fine and $98.6 million in interest.

The amount of interest owed by the defendants is set to increase every day they do not pay the fines.

New York Attorney General Letitia James, whose office brought the civil fraud case against Donald Trump, described the ruling as a "tremendous victory for this state, this nation, and for everyone who believes that we all must play by the same rules -- even former presidents."

“When powerful people cheat to get better loans, it comes at the expense of honest and hardworking people," James said in a statement. "Everyday Americans cannot lie to a bank to get a mortgage to buy a home, and if they did, our government would throw the book at them. There simply cannot be different rules for different people."

The former president is "finally facing accountability for his lying, cheating, and staggering fraud," she said.

In addition to the fines imposed on Donald Trump and his co-defendants, the judge's decision leaves the Trump Organization in a constrained position to continue operating their New York-based businesses.

While Judge Engoron backtracked on his September summary judgment ruling -- vacating the part of his order that canceled their business certificates -- Donald Trump and his sons are temporarily unable to lead their namesake company. Trump faces a three-year ban on serving as the leader of a New York company, and his sons face two-year bans.

An independent monitor will continue to oversee the company's finances for at least three years, and the company needs to install a director of compliance.

Regarding the combined $364 million owed by the defendants, experts who ABC News spoke with believe it is unlikely any of them foot the bill immediately; instead, they can cover the fine with a bond while they appeal.

Testifying for the defense, former President Trump's eldest son described his father as a real estate "visionary" who "sees the sexiness in a real estate project," creating value for the family business that cannot be captured on paper.

Donald Trump Jr. began his testimony with a quip after Judge Engoron welcomed him back to the stand following his testimony earlier in the month.

"I'd say it's good to be here, but the attorney general would probably sue me for perjury," Trump Jr. joked.

In his testimony, Trump Jr. described the Trump Organization as "a large family business," with Trump and his eldest children at the top and other executives handling many of the details.

"If there were numbers and things, I would rely on them to give me that," Trump Jr. said.

He recounted the history of the Trump Organization, beginning with his great-grandfather who he said built hotels in the Yukon Territories of Canada. His grandfather, Fred Trump, "started working on job sites around Queens, learned the trades" and eventually "created an incredible portfolio, by the time of his passing, of rental apartments in Brooklyn and Queens."

A state attorney jokingly objected that references to the 1800s were outside the statute of limitations -- then more seriously objected to the history lesson's relevance.

"I think it is relevant to get the historical perspective -- I find it interesting," Judge Engoron said in overruling the objection. "Let him go ahead and say how great the Trump Organization is."

Trump Jr. obliged.

"My father learned a lot of the business from him, but had some flair and saw New York City and Manhattan as the ultimate frontier," he said. Speaking of Trump Tower, he said, "I think it would have been one of the first, I think great, ultra-luxury real estate emerging in Manhattan."