Before today's first witness entered court, Trump attorney Chris Kise asked Judge Engoron to postpone today's proceedings after five members of the New York attorney general's team tested positive for COVID-19.

Describing the attorney general's conduct as "beyond irresponsible," Kise said that his team did not get adequate notice about the COVID exposures despite having close contact with positive individuals.

"Nothing else matters except for pursuing President Trump," Kise said. "We have the leading candidate for president of the United States in the courtroom today."

"The attorney general's office knew on Wednesday and didn't tell any of us," defense attorney Clifford Robert said. "We are truly in an outbreak."

Engoron declined to grant their requested delay.

In a statement, a spokesperson for New York Attorney General Letitia James said the state has complied with all CDC guidelines.

"Our office properly notified the court and defendants' counsel, and the court decided to proceed with trial today. If there were any concerns, defendants could wear masks today or at any point, but they have opted not to," the spokesperson said.

Trump called his former lawyer Michael Cohen a "proven liar" and "felon" as Trump entered the courtroom for his civil trial this morning.

"He's a felon, served a lot of time for lying, and we're just going to go in and see and I think you'll see that for yourself," Trump told reporters outside court.

Cohen pleaded guilty in 2018 to two separate criminal cases and eventually spent more than 13 months in prison -- but said that it was Trump who caused him to "follow a path of darkness."

-ABC News' Ricardo Montero contributed to this report.

Exiting his New York City apartment this morning, Michael Cohen told reporters he was "looking forward" to seeing Trump in court.

"It's been five years since we've been in the same room," Cohen said.

Cohen preemptively defended the credibility of his testimony and reiterated that he previously perjured himself "concert with and for the benefit of Donald J. Trump."

"My credibility should not be in question," Cohen said.

-ABC News' Eric Avram contributed to this report.

Donald Trump has arrived in court for the anticipated testimony of his former lawyer Michael Cohen.

New York Attorney General Letitia James is also attending the trial this morning.

James took her usual seat at the front of the courtroom's gallery, directly behind her team of lawyers at the counsel table.

The courtroom itself is nearly at capacity, with attendance matching the number of observers during the trial's opening statements.

Donald Trump Jr. testified he largely ignored a 2017 email from a Forbes magazine reporter who asked about the false claim that Donald Trump's triplex apartment in Trump Tower was 30,000 square feet -- about three times larger than its actual size.

Forwarded the message by a Trump Organization executive in 2017, Trump Jr. replied, "Insane amount of stuff there," according to material entered into evidence.

Asked about the email, Trump Jr. said he largely ignored the lengthy email and did not act on it.

"I don't know if I would spend hundreds of questions' worth of time answering questions from Forbes magazine," Trump Jr. said. "I have no specific recollection of doing anything with it."

Despite the error being called out, Trump Jr. and then-CFO Allen Weisselberg still signed off on Trump's 2016 financial statement that falsely claimed Trump's triplex was 30,000 square feet and worth $327 million, according to the New York attorney general's complaint.

Judge Engoron later paused the proceedings for the court's morning break. On his way out of the courtroom, Trump Jr. stopped to chat with the court's sketch artist.

"He said, 'Make me look sexy,'" the artist, Jane Rosenberg, told reporters.

Rosenberg famously sketched Trump Jr.'s father during his arraignment in the Stormy Daniels case, with her work landing on the cover of New Yorker magazine.