(CNN) CIA director nominee Rep. Mike Pompeo apologized to Sen. Dianne Feinstein in a private meeting Monday for critical comments he made about her in 2014 after she released a controversial Senate intelligence committee report detailing acts of torture by the CIA following 9/11, according to a source familiar with the issue.

Feinstein thanked Pompeo, a Kansas Republican, for his apology at the beginning of her remarks during the public portion of his confirmation hearing Thursday.

"I just want to begin by saying I really appreciate the private meeting we had," the California Democrat said. "For me, it was a clarification. I do appreciate your apology. I take it with the sincerity with which you gave it."

The source said Pompeo apologized for the personal tone of his comments two years ago that included the following lines in a press release from Pompeo, then a member of both the House intelligence committee and the special House committee on Benghazi.

"Senator Feinstein today has put American lives at risk. Our men and women who were tasked to keep us safe in the aftermath of 9/11 -- our military and our intelligence warriors -- are heroes, not pawns in some liberal game being played by the ACLU and Senator Feinstein."

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