Donald Trump said his daughter Ivanka had "long since checked out" after she rejected claims that the election was stolen.
In evidence to the Congressional committee investigating the January 6, 2021 riot at the US Capitol, Ivanka said she agreed with Bill Barr, her father's former attorney general, who called suggestions of widespread voter fraud "bull****".
In a statement on social media, Trump dismissed his daughter's evidence.
He said: "Ivanka Trump was not involved in looking at, or studying, election results.
"She had long since checked out and was, in my opinion, only trying to be respectful to Bill Barr and his position as Attorney General (he sucked!)."
Video footage of Barr's evidence to the committee was played during a prime-time hearing broadcast live for two hours on many US TV channels. Fox News did not show the proceedings live.
Barr said: "I made clear [to Trump after the election] that I did not agree with the idea of saying the election was stolen, and putting out this stuff, which I told the president was bull****. I didn't want to be part of it."
He saw "absolutely no basis for the allegations" and said they were "complete nonsense". Barr added: "I told him [Trump] it was crazy stuff."
A clip was then played from eight hours of evidence Ivanka gave to the committee in April this year.
She was asked to comment on Barr's view that there was "no fraud sufficient to overturn the election", and whether it affected her perspective.
Ivanka said: "It affected my perspective. I respect Attorney General Barr. So I accepted what he was saying."
A clip was also shown of Jared Kushner's evidence, in which he was asked about threats by the White House Counsel to resign over Trump's fraud claims.
Kushner said: "I kind of took it up to be just whining, to be honest with you."
The committee hearing followed a year-long investigation which included 1000 interviews.
The nine-member committee consists of seven Democrat members of Congress, and two Republicans who have been highly critical of Trump.
Trump, who was not represented at the hearing, dismissed them as "political thugs".
Committee chairman Bennie Thompson, a Democrat from Mississippi, said January 6 was the "culmination of an attempted coup" and accused Trump of being "at the centre of this conspiracy". He added: "It was Trump's last stand."
Liz Cheney, the Republican vice-chair of the committee, said: "President Trump summoned the mob, assembled the mob and lit the flame of this attack."
She said Trump was aware of the rioters' chants to "hang Mike Pence", and that he responded "Maybe our supporters have the right idea" and that Pence "deserves" it.
Responding to that allegation on social media, Trump said: "I NEVER said, or even thought of saying, 'Hang Mike Pence'."
The committee played 12 minutes of video footage, some of it filmed by British documentary maker Nick Quested, showing the extent of the violence.
Quested, appearing in person, told the hearing: "I documented the crowd turn from protesters to rioters to insurrectionists. I was surprised at the size of the group, the anger and the profanity."
Caroline Edwards, a female police officer who was knocked unconscious while battling the mob, also gave evidence.
She said: "What I saw was just a war scene. It was something like I had seen out of the movies. I couldn't believe my eyes. There were officers on the ground. They were bleeding, they were throwing up.