A CNN anchor acknowledged on Sunday that "we can't actually know what was said" in a 2018 meeting between Sen. Elizabeth Warren, D-Mass., and Sen. Bernie Sanders, I-Vt., that led to the spat at last week's Democratic debate.

On Sunday's "State of the Union," fill-in anchor Brianna Keilar held a panel about the dustup that occurred between the progressive candidates that began last Monday with CNN's report that Sanders supposedly told Warren during a 2018 meeting that a woman couldn't win the presidency, which he had flatly denied following the report and at the debate while Warren simply stated she "disagreed," affirming the claim that was made in the original story.

However, panelist Mary Katharine Ham expressed strong skepticism toward Warren's claim.

"I'm willing to believe in a lot of unsavory things about Senator Sanders. It doesn't ring true to me that he believes a woman can't win the presidency. I don't think he's changed his mind about that," Ham said. "There's two people in the room. I don't want to act naive where this story might have come from, probably not from the side that looks really bad during this exchange. And he should've just said, 'Well, you called me a sexist on national TV.'"

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She continued. "We don't actually know, but we do know that Senator Warren has stretched the truth on several major stories including her heritage, the wine cave most recently, her employment in the past. That should be part of the calculation here and the fact that this story seems to widely benefit her and give her this moment in the spotlight to make the speech that she made."

"We can't actually know what was said," Keilar said in agreement before pivoting the conversation.

This position was certainly not the one that was taken at last Tuesday's debate where CNN moderator Abby Phillip had been accused of "siding" with Warren over Sanders.

"CNN reported yesterday that -- and Senator Warren confirmed in a statement -- that in 2018 you told her that you did not believe that a woman can win the election. Why did you say that?" Phillip asked.

"Well, as a matter of fact, I didn't say it," Sanders sharply replied. "Anybody who knows me knows that it's incomprehensible that I would think that a woman cannot be president of the United States. Go to YouTube today. There's some video of me 30 years ago talking about how a woman could become president of the United States."

Sanders then pointed to his attempt to "draft" Warren to run for president in 2016 and vowed to support the eventual Democratic nominee, including female candidates like Warren and Sen. Amy Klobuchar, D-Minn.

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"Senator Sanders, I do want to be clear here. You're saying that you never told Senator Warren that a woman could not win the election," Phillip followed.

"That is correct," Sanders answered.

"Senator Warren, what did you think when Senator Sanders told you a woman could not win an election?" Phillip then asked the progressive rival, which sparked audible laughs in the auditorium and a shake of the head from Sanders.