Former vice president Joe Biden holds a campaign event in Dubuque, Iowa, on Tuesday. (Jonathan Ernst/Reuters)

Former vice president Joe Biden on Tuesday disputed President Trump’s explanation for his “very fine people on both sides” remark about the 2017 white-nationalist rally in Charlottesville, telling a crowd in Iowa, “Hatred was on the march, and he knew it.”

After Biden announced his 2020 White House bid with a video in which he criticized Trump for the remarks, the president last week claimed that his statement was a reference not to the torch-bearing white-supremacist marchers but rather to people who had opposed the removal of a statue of Confederate Gen. Robert E. Lee.

The media had misunderstood, Trump argued. But Biden told supporters Tuesday that Trump’s version of events was “nonsense.”

“He now has come down and doubled down on concocting a phony story about how these violent thugs only wanted to protect the statue of Robert E. Lee. Give me a break. No, no, I mean, this is — enough’s enough, man,” Biden said at a campaign event in Cedar Rapids.

As murmurs rippled through the crowd, Biden continued. “The very rally was advertised — advertised — as a white supremacist rally. Anti-Semitic chants were clear. Hatred was on the march, and he knew it.”

Biden’s remarks are the latest indication that his campaign intends to continue hammering Trump on the issue, at a time when white nationalism has been pushed to the forefront of the 2020 race.

The 2017 rally in Charlottesville was organized by self-proclaimed white nationalist Richard Spencer, and many of the demonstrators chanted anti-Semitic slogans such as “Jews will not replace us.”

James Alex Fields Jr., who killed Heather Heyer and injured 35 others when he plowed his car into a group of counterprotesters at the rally, pleaded guilty to hate crimes in federal court in March.

Those events were front and center in Biden’s announcement video last week. The former vice president said Trump’s “very fine people” comments about the rally had “shocked the conscience of this nation” — prompting Trump to defend his statement anew, a strategy that even some Republicans have acknowledged carries political risk for the president.

In an exchange with reporters on the day of Biden’s announcement, Trump said that he had been referring to “people that went because they felt very strongly about the monument to Robert E. Lee, a great general.”

Trump did mention Lee in his initial defense of his remark at a news conference on Aug. 15, 2017, days after the rally. But until the past week, Lee and the battle over Confederate statues had rarely been mentioned by Trump’s surrogates when they defended his handling of the matter over the past two years.

On the one-year anniversary of the rally, Trump counselor Kellyanne Conway was repeatedly asked for an explanation by host Jon Karl during an interview on ABC News’s “This Week.”

“Who were the very fine people on the side of the neo-Nazis?” Karl asked.

Conway did not answer the question, instead noting that Trump had denounced the white supremacists who organized the march.

Marc Short, the former White House legislative affairs director who now serves as Vice President Pence’s chief of staff, was also asked about Trump’s comment during a roundtable on the program.

Short noted that Trump had denounced the white nationalists but also said it was “wrong” of him to have referred to “very fine people.”

“That was mixed messaging, and that was unfortunate,” Short said.

Colby Itkowitz contributed to this report.