Rick Gates testified on Tuesday that he stole nearly $3 million from his former boss, Paul Manafort, to finance an extramarital affair ten years ago.

Gates said his wife knew about the affair, which Manafort's lawyer repeatedly referred to as being part of Gates' "secret life."

"After all the lies you've told, you expect this jury to believe you?" Manafort's lawyer asked Gates at one point.

"Yes," Gates replied. He added that he was "here to tell the truth" and to take responsibility for his actions.

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ALEXANDRIA, Virginia — Rick Gates, Paul Manafort’s former right hand man, admitted Tuesday that he cheated Manafort out of nearly $3 million to fund an extramarital affair.

Gates’ acknowledgement came as he was testifying against Manafort as part of a high-stakes criminal trial against Manafort — the former chairman of President Donald Trump's campaign, and the subject of two indictments from the special counsel Robert Mueller.

The one at the center of Tuesday's trial charges Manafort with tax fraud, bank fraud, and a failure to report foreign bank accounts. Gates was initially a codefendant in both indictments against Manafort, but he struck a plea deal with prosecutors in February that included testifying against Manafort. He is now the government's star witness in the Manafort case.

Gates' admission about his affair came as Manafort's lawyer, Kevin Downing, was grilling him as part of a lengthy cross-examination on Tuesday.

Downing asked Gates at one point, "There was another Richard Gates, isn't that right? A secret Richard Gates?"

Gates then admitted, in subdued tones, that he'd had "another relationship" a decade ago.

All the while, Manafort glared at Gates while Gates purposefully avoided his former boss's gaze.

Gates added that the affair took place in London for about two months. He said he embezzled money from Manafort to pay for the affair, which included flying first class, staying in high end hotels, and keeping a separate apartment in London.

Gates said he would often stay there en route to Ukraine, where he frequently traveled to do political consulting work for Manafort's firm, Davis Manafort Partners International.

Gates said later on that his wife knew about the affair, which Downing repeatedly referred to as part of Gates' "secret life."

The line of questioning tied into the central facet of the defense's strategy in the Manafort trial: to throw a wrench into Gates' credibility.

To that end, Downing asked Gates on Tuesday: "After all the lies you've told, you expect this jury to believe you?"

"Yes," Gates replied. He added that he was "here to tell the truth" and to take responsibility for his actions.