Prosecutors and staff from the Manhattan district attorney's office have arrived in court.

Prosecutors Joshua Steinglass, Becky Mangold and Christopher Conroy are seated at counsel table.

Manhattan District Attorney Alvin Bragg is not present in court this morning.

Michael Cohen, the prosecution's star witness in Donald Trump's hush money trial, is expected to take the stand Monday, according to multiple sources familiar with the case.

Trump's former attorney and "fixer," Cohen made the $130,000 payment to Stormy Daniels that sits at the center of the case, in order to buy her silence and help Trump's electoral prospects in the 2016 presidential election.

Prosecutors accuse of Trump falsifying business records when he repaid Cohen the $130,000.

Former Trump White House aide Madeleine Westerhout is set to resume her testimony this morning in former President Donald Trump's New York criminal trial.

For prosecutors, Westerhout's testimony yesterday offered a detailed picture of how Trump approached his personal finances while serving as president -- including how he signed personal checks for his then-attorney Michael Cohen and others.

Defense attorneys, meanwhile, appeared to use Westerhout to highlight Trump's character following hours of abrasive testimony from Stormy Daniels.

"He never once made me feel like I didn't deserve that job and I didn't belong there, especially in an office filled with older men," Westerhout told jurors about working by Trump's side for over two years. "He was a really good boss. I hope he respected me in my job, and I just found him very enjoyable to work for."

Westerhout at one point broke down in tears on the witness stand while recounting to the jury how she lost her job after she shared private details of Trump's family with reporters at an off-the-record dinner.

"That mistake, eventually -- ultimately, cost me my job, and I am very regretful of my youthful indiscretion," Westerhout said while crying.

Judge Juan Merchan dismissed court for the day following the late hearing.

Trump, speaking to reporters on his way out of the courtroom, railed against the judge.

"Everybody saw what happened today -- I don't think we have to do any expert explaining," Trump said. "I'm not allowed to anyway because this judge is corrupt," he said, criticizing Merchan -- who is not protected by the limited gag order in the case.

"I got to get back on the campaign trail. I'm not supposed to be here. We are so innocent," Trump said.

-ABC News' Kelsey Walsh and Mike Pappano

Former President Trump, on his way out of the courtroom at the end of the day's proceedings, assailed Judge Juan Merchan for declining to gag upcoming witness Michael Cohen for remarks he's been making about Trump and the case on social media.

"There is no gag order to Michael Cohen. What the judge did was amazing, actually was amazing," Trump said of Merchan telling prosecutors to ask Cohen to stop making comments.

"Everybody can say whatever they want. They can say whatever they want. I'm not allowed to say anything about anybody," Trump said.

Trump also reiterated that his repayments to Cohen for Stormy Daniels' hush payment were properly recorded in his company's ledger. Prosecutors have said the repayments were unlawfully marked as a "legal expense" to conceal their true nature.

"I didn't do the bookkeeping. I didn't even know about it, but a very good bookkeeper marked a legal expense down as a legal expense," Trump said. "They didn't call it construction. They didn't call it building something or concrete or electrical cost. They called it, very simply, a legal expense to a lawyer -- who's a lawyer, not a fixer -- he's a lawyer."

"A legal expense to a lawyer," Trump repeated.

-ABC News' Kelsey Walsh and Mike Pappano