Washington (CNN) Rod Rosenstein took aim at James Comey Monday, calling him a "partisan pundit" in a speech that included the most public retelling yet of the twists and turns of the Russia investigation by the man who oversaw it.

Speaking to a group of business and civic leaders in Baltimore, the former deputy attorney general -- just days removed from a tumultuous tenure at the Department of Justice -- recounted how he had prepared a memo in 2017 that supported President Donald Trump's firing of Comey, then the FBI director, and defended his decision to appoint Robert Mueller as a special counsel in the wake of that firing.

Rosenstein also responded directly to a barb from the former FBI director, who said at a CNN town hall last week that Rosenstein's character wasn't strong and that his soul had been "eaten" by his time in the Trump administration.

"Now the former director seems to be acting as a partisan pundit, selling books and earning speaking fees while speculating about the strength of my character and the fate of my immortal soul. I kid you not. That is disappointing," Rosenstein said.

In his speech before a crowd of nearly 1,000 people at the annual Greater Baltimore Committee dinner, Rosenstein acknowledged the unusual role he played in the drama of Trump's Washington -- as a Republican held up by the left for stewarding the Mueller probe.

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