White House press secretary Sarah Sanders on Friday repeated her claim that it was "a slip of the tongue" when she told reporters that "countless" FBI agents had told the White House that they had lost confidence in James Comey.

Special counsel Robert Mueller's report, released Thursday, said that Sanders had simply made the assertion up in 2017.

"I said a slip of the tongue was in using the word 'countless,' but there were a number of FBI, both former and current, that agreed with the president's decision and they've continued to speak out and say that," Sanders said during an interview on ABC’s "GMA."

When pressed by host George Stephanopoulos about why she "can’t acknowledge that what you said then was not true," Sanders became defensive.

"I said that the word I used 'countless', and also if you look in what's in quotations from me it's that and it was in the heat of moment, meaning that it wasn't a scripted talking point," she said.

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She added that she was "sorry that I wasn't a robot like the Democratic Party that went out for two and a half years and stated time and time again that there was definitely Russian collusion between the president and his campaign."

Mueller's report referred to a May 10, 2017, news conference at which Sanders, then the White House deputy press secretary, told reporters that "countless" FBI agents had told the White House that they had lost confidence in Comey, who had been fired as FBI director the day before by President Donald Trump.

Mueller’s report found that Sanders, since promoted to press secretary, told investigators she had no evidence to make that claim. Sanders, who was interviewed by Mueller's team as part of its investigation into Russian interference in the 2016 election, said the claim was a "slip of the tongue."