Former director of the Office of Government Ethics (OGE) Walter Shaub on Wednesday explained the significance of a letter that accompanied President Donald Trump’s 2017 financial disclosure report sent to Deputy Attorney General Rod Rosenstein.

OGE Acting Director David Apol sent the letter to Rosenstein after Trump acknowledged a payment to his lawyer Michael Cohen. The president had previously failed to report that on his financial disclosure form.

“… You may find the disclosure relevant to any inquiry you may be pursuing regarding the President’s prior report that was signed on June 14, 2017,” Apol wrote.

Shaub, who resigned from the OGE last year, detailed why Apol’s letter is a very big deal for Trump.

“This is a very big development and apparently the Office of Government Ethics' current acting director believes so, too,” Shaub said. “His letter to Rod Rosenstein is tantamount to a criminal referral, and that's because it would be a crime to knowingly and willfully omit any required information from a report.”

Shaub noted that despite claims from Trump and his attorney Rudy Giuliani that the president did not know about the debt, “on the form itself President Trump acknowledged that Cohen had been asking him for reimbursement and he did make the reimbursement.”

CNN correspondent Brianna Keilar then asked Shaub about a “bizarre encounter” he had with Trump’s financial disclosure form during his time at the OGE.

“Let me note the only reason I can talk about this is because we wound up having to release a letter subject to a Freedom of Information Act request,” Shaub said.

Shaub explained that an attorney for Trump visited OGE last year "and sat across the table from me and asked that President Trump not have to certify that his financial disclosure report was true.”

“Now, there have been millions, literally millions of financial disclosure reports filed and they're as individual as snowflakes,” Shaub continued. “They only have one thing in common and that is that every one of them, the filer certified that the contents are true. And the request was that the president be the first person in history to file a financial disclosure report without having to certify it was true. And it was a breathtaking, surreal moment, and we refused to grant that request. And now I'm glad that we did because he certified his report was, quote, correct and complete.”

Watch the video below, via CNN: