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.

Citing their ethical obligations, lawyers for the defendants in Donald Trump's civil fraud trial declined to provide details about "rumors of any kind" involving former Trump Organization CFO Allen Weisselberg and urged Judge Arthur Engoron to make a decision solely based on the evidence presented at trial, after Engoron asked them to weigh in on public reports that Weisselberg was engaged in plea talks with the Manhattan DA's office to resolve a potential perjury charge.

In a letter submitted to Judge Engoron Wednesday, defense attorney Clifford Robert urged the judge to strictly consider the record from the trial in his final decision, describing his request to provide information about Weisselberg based on a New York Times article "unprecedented, inappropriate and troubling."

"The Article simply does not provide any principled basis for the Court to reopen the record or question the veracity of Mr. Weisselberg's testimony in this case. Indeed, we respectfully submit that the Court's request for comment on this speculative media account is unprecedented, inappropriate, and troubling," Robert wrote.

In a separate letter, Alina Habba -- who represents Weisselberg in the civil case but is not his criminal defense lawyer -- declined to provide any information about the potential perjury and argued that no further action was needed on the matter.

"The New York Times article is neither admissible nor reliable, and it should not be considered in Your Honor's determination as to the merits of this case," Habba wrote. "We urge you to render your decision based solely on the evidence now before you."

"Court decisions are supposed to be made based on the evidence at trial, not on media speculation," defense attorney Chris Kise said in a statement.