Pelosi condemns Trump amid newly reported details of his inaction on Jan. 6

Former House Speaker Nancy Pelosi on Sunday lambasted former President Donald Trump for his reported inaction to quell the violence at the U.S. Capitol on Jan. 6, 2021.

"He incited an insurrection," the California Democrat told ABC News "This Week" anchor George Stephanopoulos one day after the three-year mark of the riot.

Trump has long maintained he did nothing wrong during Jan. 6 and has downplayed the chaos of that day.

Pelosi invoked the nation's history as she argued the stakes were high heading into the 2024 race, in which Trump is seeking to return to the White House against President Joe Biden.

"I'm proud of the national anthem. And in it, it says 'proof through the night that our flag was still there.' We have to prove through this campaign in the night that our flag is still there with liberty and justice for all and not have an acceptance of Confederate flags under [the] Lincoln dome [at the Capitol] with a president sitting in the White House doing nothing to stop the violence," Pelosi said. "He talks about the big steal as he can engages in the big lie."

Pelosi's comments come after new reporting from ABC News on Sunday on previously undisclosed details about how Trump had remained uninterested in getting involved to stop the violence during the riot, according to sources familiar with testimony in the special counsel’s investigation of Trump.

Trump has pleaded not guilty to the felony charges he faces in his federal election subversion indictment. He has denied all wrongdoing and claimed political persecution, which prosecutors reject.

According to ABC News' new report, sources said Trump's former deputy chief of staff, Dan Scavino, told special counsel Jack Smith's investigators that Trump "was just not interested" in doing more to stop the mob that went on to ransack the Capitol in 2021.

Additionally, sources said that when Trump was informed that then-Vice President Mike Pence had to be transported from the halls of the Capitol to a secure location, Trump responded, "So what?"

A spokesperson for Trump told ABC News in response to the new reporting, in part, "Media fascination with second-hand hearsay shows just how weak the Witch-Hunt against President Trump is."

An attorney for Scavino declined to comment to ABC News for Sunday's new report. The Trump spokesperson said in that story that Scavino was "one of President Trump's longest-serving, most loyal allies."

Appearing on "This Week," Pelosi seized on the details to note that many of the revelations that have come out about Trump's efforts to overturn the 2020 election results and his actions on Jan. 6, 2021, have come from Republicans.

"What's interesting about it all is that in every case, every piece of this, whether it was in our case, in terms of the Electoral College, whether it was what happened with the Jan. 6 select committee or this testimony now, is all coming from Republicans," she said, adding, "It's very clear what happened that day."

Still, Stephanopoulos noted, recent polling has showed a sizeable chunk of Republicans continue to falsely believe Trump won the 2020 election and that the FBI instigated the violence on Jan. 6.

"It's a challenge that we have in our country," Pelosi acknowledged. "We have people who don't want to believe the truth or whatever attitudes they have otherwise. But again, during this period, this campaign year, it behooves us to speak with respect for all concerns in a unified way to bring people together. But there is no way that anybody can think that that assault on the Constitution ... it cannot stand. He [Trump] is not above the law."

When pressed by Stephanopoulos over whether Trump should be barred from running for president again under the 14th Amendment, a part of which prohibits insurrectionists from running for federal office, Pelosi demurred, saying the courts will ultimately have to rule on the matter.

But in her view, she said, "I think that he engaged in an insurrection."

Stephanopoulos also separately asked Pelosi about Republicans' demands for major immigration reform as part of any other movement on the White House's pending national security proposal, including recent threats that House GOP hard-liners could vote against a bill to fund the government if a deal is not reached on beefing up border security.

"We know what works. It's not rocket science," House Speaker Mike Johnson said last week during a trip to the southern border to spotlight the high amount of illegal immigration.

Responding to that on "This Week," Pelosi said, "We can't have a government shutdown. Let's be grown-up about how we deal with our responsibilities."

"We have to handle this with care," she said. "We must secure our border. That's for sure. There's no question about that. But we also must honor our responsibilities in terms of asylum and the rest, and the president has that in his proposal."