Michael Cohen is gearing up to testify before Congress on Wednesday regarding his relationship with President Donald Trump.

Democrats on the House Oversight Committee plan to question Cohen on a wide array of subjects, including several hush-money payments made to women during the 2016 election, as well as Trump's business dealings, according to an internal committee memo seen by INSIDER.

Cohen, meanwhile, will accuse the president of engaging in criminal conduct while in office, The Wall Street Journal reported. The accusations are related to the hush-money payment Cohen facilitated to the porn star Stormy Daniels in exchange for her silence about an affair she says she had with Trump, which Trump denies.

The Journal quoted a source as saying Cohen also planned to provide evidence of "lies, racism, and cheating" by Trump.

Cohen has never publicly accused Trump of criminal conduct while serving as president.

Michael Cohen, President Donald Trump's former lawyer and longtime fixer, is gearing up this week for three consecutive days of testimony before Congress.

On Tuesday, he will appear before the Senate Intelligence Committee for a closed-door hearing, and he will have a second closed-door hearing before the House Intelligence Committee on Thursday.

But by far the most highly anticipated is Cohen's scheduled testimony before the House Oversight Committee, which is slated to take place Wednesday in a public setting.

According to an internal committee memo seen by INSIDER, Democrats on the panel plan to question Cohen extensively about several hush-money payments made during the 2016 election to women who said they had affairs with Trump. The president denies the affairs and initially denied knowing anything about the payments.

Cohen, meanwhile, plans to accuse Trump of engaging in criminal conduct while in office, The Wall Street Journal reported Tuesday.

The accusations are related to a hush-money payment that Cohen facilitated to Stormy Daniels, the porn star who says she had an affair with Trump about a decade ago, The Journal reported.

The Journal story cited an unnamed person familiar with Cohen's planned testimony to Congress on Wednesday.

The source did not offer other specifics about what the accusation entailed.

Such testimony would mark the first time Cohen accused Trump of criminal conduct while serving as president. But Cohen has previously implicated Trump in campaign finance violations. In December, during Cohen's sentencing hearing, a federal judge also said in open court that Trump had directed his then-lawyer to commit a felony during the election.

Read more: Here are the partisan lawmakers to watch on both the left and the right when Michael Cohen gives his highly anticipated testimony before Congress

Cohen and Trump. Jonathan Ernst/Reuters

Democrats on the House Oversight Committee also plan to question Cohen extensively about Trump's business dealings and his compliance with tax laws, according to the internal memo. Cohen is expected to provide some of Trump's private financial statements to the committee and give what The Journal described as "behind-the-scenes" details of working for the president.

He will say Trump at times inflated or deflated his net worth for business and personal purposes, including the avoidance of property taxes, The Journal reported.

He also reportedly plans to provide evidence of "lies, racism, and cheating" by Trump, including allegedly racist remarks about African-Americans' intelligence and lifestyle choices.

Cohen has pleaded guilty to multiple federal crimes in two separate investigations. Last year, he pleaded guilty to tax evasion, bank fraud, and campaign finance violations as part of a Manhattan US attorney's office investigation into his and Trump's business dealings before the election.

He also later pleaded guilty in the special counsel Robert Mueller's Russia investigation to one count of lying to Congress about the now defunct Trump Tower Moscow project.

Read more: Michael Cohen's latest plea deal shows Mueller's 'starting to finally get to the truth' behind Trump and Russia

Michael Cohen. AP Photo/Julie Jacobson

Though the president initially defended Cohen following an FBI raid on his property, the White House subsequently began distancing itself from Trump's longtime lawyer and fixer. Cohen reportedly felt betrayed by the president and decided to cooperate with prosecutors soon after.

Cohen served as the Trump Organization's lead lawyer for over a decade before leaving the company in 2017 to be Trump's personal lawyer. His proximity to Trump, as well as his elevated position on the campaign and in Trump's personal life, makes him one of the most dangerous cooperators against the president to date, legal scholars told INSIDER last year.

White House press secretary Sarah Huckabee Sanders lashed out at The Journal's report on Tuesday morning, calling Cohen a "disgraced felon" and saying it was "laughable" that people would listen to his "lies."

The president and his associates have frequently characterized Cohen as a liar since the lawyer stopped working for the president. Republican lawmakers on the House Oversight Committee also plan to paint Cohen as a liar whose statements can't be trusted.

But legal experts said their attacks may be undermined if Cohen can support his allegations with documentary evidence, as he reportedly plans to do.

Cohen is due to begin serving a three-year prison sentence on March 6 over an array of financial crimes and after he pleaded guilty to one count of lying to Congress about various aspects of the Trump Tower Moscow deal when he testified before the House Intelligence Committee in 2017.