NEW YORK — US President Donald Trump sparked another political firestorm on Tuesday when he doubled down on his initial response to the violent white supremacist rally in Charlottesville that ended in bloodshed, saying there was "blame on both sides".

The Republican president -- who one day ago solemnly denounced racism and singled out the Ku Klux Klan and neo-Nazis as "criminals and thugs" -- also hit out at the "alt-left" over the weekend melee.

Trump has faced days of criticism from across the political spectrum over his reaction to Saturday’s unrest in the Virginia college town, where a rally by neo-Nazis and white supremacists over the removal of a Confederate statue erupted in clashes with counter-demonstrators.

The violent fracas ended in bloodshed when a 20-year-old suspected Nazi sympathiser, James Fields, plowed his car into a crowd of anti-racism protesters, leaving one woman dead and 19 others injured.

In a rowdy exchange with journalists at Trump Tower in New York, Trump made clear on Tuesday that he was fed up with continued questioning about the issue.

"I think there is blame on both sides," Trump said.

As he spoke, his new White House Chief of Staff John Kelly, a former Marine general, appeared displeased during the president’s long tirade, standing rigidly.

"You had a group on one side that was bad, and you had a group on the other side that was also very violent. And nobody wants to say that, but I’ll say it right now," Trump continued.

"What about the alt-left that came charging... at the, as you say, the alt-right? Do they have any semblance of guilt? (...) There are two sides to a story."

’No words’

Trump’s comments were immediately welcomed by David Duke, a former "grand wizard" of the Ku Klux Klan and a key figure at Saturday’s rally.

"Thank you President Trump for your honesty & courage to tell the truth about #Charlottesville & condemn the leftist terrorists," Duke tweeted.

But on the political left, the president’s words were met with indignation.

"Charlottesville violence was fueled by one side: white supremacists spreading racism, intolerance & intimidation. Those are the facts," said Tim Kaine, a former Democratic vice presidential candidate and senator from Virginia.

The state’s other Democratic senator, Mark Warner, tweeted: "No words." Trump’s fellow Republicans also didn’t mince words.

"We must be clear. White supremacy is repulsive," Republican House Speaker Paul Ryan wrote on Twitter.

"This bigotry is counter to all this country stands for. There can be no moral ambiguity."

And the condemnations also spilled beyond the political realm.

NBA superstar LeBron James tweeted: "Hate has always existed in America.

Yes we know that but Donald Trump just made it fashionable again!"

After the contentious press conference, the head of the main US labor union, the AFL-CIO, joined several high-powered executives in stepping down from Trump’s manufacturing advisory panel.

"President Trump’s remarks today repudiate his forced remarks yesterday about the KKK and neo-Nazis," union leader Richard Trumka said in a statement.

"We must resign on behalf of America’s working people, who reject all notions of legitimacy of these bigoted groups."

Outside Trump Tower where the president spoke, hundreds of people protested to denounce racism. They were surrounded by police officers to prevent clashes with a handful of Trump supporters nearby. — AFP