“It’s been an amazing four years,” Mr Trump told the crowd at his last Christmas party in the White House.
“We’re trying to do another four years. Otherwise, I’ll see you in four years," he told the reception which included many Republican National Committee members.
The video of Mr Trump’s appearance was streamed live on Facebook by one attendee, Pam Pollard, who is national committeewoman for the Oklahoma GOP.
It showed dozens of people crammed into the Cross Hall of the White House state floor, standing closely together. Many seen in the video were not wearing masks with some coughing.
Watch: Trump says 'certainly will' leave WH if Biden wins
The Trumps began hosting holiday receptions this week, intent on celebrating a final season before Mr Trump leaves office on January 20.
According to social media postings the events have featured large crowds of often maskless attendees gathered indoors — violating the very public health guidance the U.S. government has pressed the nation to follow this holiday season as cases of COVID-19 skyrocket across the country.
In the video, Mr Trump is heard continuing to air baseless allegations of election fraud to explain his defeat by President-elect Joe Biden.
“It’s certainly an unusual year. We won an election. But they don’t like that,” Mr Trump told the group, adding: “I call it a rigged election, and I always will.”
Mr Barr said US attorneys and FBI agents have been working to follow up specific complaints and information they had received but found no evidence that would change the vote’s outcome.
"To date, we have not seen fraud on a scale that could have effected a different outcome in the election," Mr Barr said.
Only 50 days until we get to call @JoeBiden President of the United States.
— Kamala Harris (@KamalaHarris) December 1, 2020
The White House has been the site of at least one suspected Covid-19 superspreader event, and dozens of the president’s aides, campaign staffers and allies have tested positive in numerous outbreaks. Mr Trump himself was hospitalised for the virus in October, and the first lady and two of his sons have tested positive.
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