When he was president, Barack Obama called then-presidential candidate Donald Trump a "fascist" during a phone call with U.S. Sen. Tim Kaine, who was Hillary Clinton's vice presidential running mate during the 2016 campaign, Kaine noted in a clip from an upcoming documentary about Clinton, NBC News reported.

What are the details?

Kaine recalled the phone conversation amid an exchange with Clinton caught on camera in 2016, the network said.

"President Obama called me last night and said: 'Tim, remember, this is no time to be a purist. You've got to keep a fascist out of the White House,'" the Virginia senator recounted, adding that Obama "knows me, and he knows that I could tend to err," NBC News said.



Clinton said, "I echo that sentiment" before putting her hands to her chest and adding, "But that's really — the weight of our responsibility is so huge," the network reported.

Kaine's wife, Anne Holton, also was present, NBC News said.

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The clip appears in an episode of "Hillary," a four-part documentary series that will be available on Hulu on March 6. The docuseries, which premieres at the Sundance Film Festival on Saturday at a screening Clinton was scheduled to attend, chronicles her early life, rise to national prominence and political career.



NBC News was given access to the series this week. Nanette Burstein, an Oscar-nominated filmmaker who directed "Hillary," confirmed in an email that the clip of Kaine was recorded by a camera team hired by the Clinton campaign.



The date and location of the conversation are not clear.

Kaine's recollection of Obama calling Trump a fascist represents a more pointed offensive from Obama than what he said in public regarding Trump during and after the campaign, NBC News said.

The network added that Obama's communications director declined to comment about the documentary and that Kaine's office and Clinton's spokesman did not respond to requests for comment.