STORY: Donald Trump's one-time personal lawyer Michael Cohen was back on the witness stand on Tuesday.

And he detailed a 2017 Oval Office meeting where Trump, who was then the newly-elected U.S. president, agreed to a plan to secretly reimburse Cohen for a hush money payment the attorney made to a porn star.

Cohen is the prosecution's star witness at Trump's criminal trial in New York, where the ex-president is accused of illegally falsifying business records to hide the payment to Stormy Daniels.

Prosecutors say Trump wanted to silence her claims about a 2006 sexual encounter as he campaigned for president in 2016.

"It's a scam. It's election interference at a level that's never taken place before."

Trump has denied the affair, pleaded not guilty, and called the prosecution a political effort to derail his current presidential campaign.

In his first day as a witness on Monday, Cohen laid out in painstaking detail how Trump ordered him to pay Stormy Daniels. That $130,000 payment is at the heart of Trump's historic trial, now in its fifth week.

On Tuesday, Cohen testified about a series of invoices and checks - some signed by Trump himself - that Cohen said were falsely for recorded legal services.

While Cohen testified, a mid-level appeals court denied Trump's latest effort to throw out a gag order that Trump asserted violated his right to free speech.

Justice Juan Merchan's order allows Trump to criticize the judge, District Attorney Alvin Bragg, and complain that the case is a witch-hunt. But it prohibits Trump from commenting about potential witnesses, jurors, court staff, or family members of those connected to the case.

So a high-level Trump ally did just that instead: Republican House Speaker Mike Johnson spoke outside the courthouse on Tuesday, taking aim at Michael Cohen.

"This is a man who is clearly on a mission for personal revenge..."

He also railed against the judge's daughter.

"The judge's own daughter is making millions of dollars doing online fundraising for Democrats..."

Trump is facing three other criminal cases, but it's unclear if any others will go to trial before the November election. He has pleaded not guilty in all of them.