Democratic congresswoman Ilhan Omar branded Donald Trump a "fascist" on Thursday as the president sought to distance himself from mocking chants of "Send her back!" directed at the Somali-born lawmaker by his supporters.
"We have said this president is racist, we have condemned his racist remarks," said Omar, one of two Muslim women in Congress. "I believe he is a fascist."
Chants of "Send her back!" broke out at Trump's "Make America Great Again" rally in Greenville, North Carolina, overnight as he attacked Omar and three other ethnic minority Democratic congresswomen.
Trump claimed to reporters in the Oval Office on Thursday that he was not pleased by the taunts.
"I was not happy when I heard that chant," he said. "I didn't like that they did it, and I started speaking quickly."
Television footage showed, however, that Trump let the chant continue for more than 10 seconds before he resumed speaking.
Trump was rebuked by the Democratic-controlled House of Representatives on Tuesday for "racist comments" for saying the four congresswomen should "go back" to their countries of origin if they are not happy in the United States.
But he made it clear at the rally that he plans to make inflammatory attacks on Omar and her three left-leaning fellow Democrats a centrepiece of his 2020 re-election strategy.
Without a Democratic presidential candidate to focus on yet, the Republican chief executive is seeking to make the minority lawmakers known as the "Squad" the face of the Democratic Party.
The first-term lawmakers — all but one of whom, Omar, were born in the United States — are of Hispanic, Arab, Somali, and African-American descent.
To the delight of his thousands of supporters in Greenville, Trump described Omar and the other Democrats as "left-wing ideologues (who) see our nation as a force of evil".
"A vote for any Democrat in 2020 is a vote for the rise of radical socialism and the destruction of the American Dream — frankly the destruction of our country," Trump said.
The crowd responded to his attacks with cries of "Send her back!" reminiscent of the "Lock her up!" chants directed in 2016 at the Democratic candidate, Hillary Clinton.
Some Republicans have urged Trump to tone down the rhetoric but the president clearly believes — despite the risk of inflaming racial tensions and widening the partisan divide — that he has latched on to a winning strategy.
Trump tapped into a vein of grievance among white blue-collar and rural Americans to eke out a narrow victory in 2016 and he's hoping to do the same again next year.
"He's rallying his base," said Wendy Schiller, a professor of political science at Brown University. "His electoral strategy is to divide and conquer."
"He needs every single one of those voters who voted for him in 2016 to vote for him again," Schiller said. "He thinks this is a way to get them riled up now."
"So it's a smart strategy for him to make these four women the face of the Democratic Party, in his mind, in terms of maintaining the votes that he got in 2016."
Trump won 57 percent of white voters in 2016 while Clinton won 37 percent.
Some 70 percent of the electorate next year is expected to be white. African-Americans, Hispanics, and other minorities account for the rest and tend to vote for Democrats.
Larry Sabato, director of the Center for Politics at the University of Virginia, said Trump's attacks on the "Squad" were aimed squarely at the white voters who delivered him the White House in 2016.
"It's a cynical strategy," Sabato said. "Most presidents wouldn't do it because they don't want to be tagged as racists by history. But Donald Trump doesn't give a damn as long as he wins."
Several of the Democratic 2020 presidential hopefuls condemned Trump's remarks.
"It's vile. It's cowardly. It's xenophobic. It's racist," said California Senator Kamala Harris. "It's time to get Trump out of office and unite the country."
Republican reaction has been more muted but some were speaking out.
"I deeply disagree with the extreme left & have been disgusted by their tone," said Representative Adam Kinzinger of Illinois.
"I woke up today equally disgusted — chants like 'send her back' are ugly, wrong, & would send chills down the spines of our Founding Fathers.
"This ugliness must end, or we risk our great union."