United States President Donald Trump has said both sides were to blame in the clashes in Virginia over the weekend, adding that protesters on the political left violently attacked white nationalists rallying against a decision to remove a Confederate statue.

Key points: Donald Trump insists anti-racism protesters as much to blame as white supremacists

Donald Trump insists anti-racism protesters as much to blame as white supremacists Claims left-wing protesters "came violently attacking the other group"

Claims left-wing protesters "came violently attacking the other group" Says some facts about Saturday's violence are still not known

Mr Trump was sharply criticised for his initial comments blaming "many sides" for the violence in Charlottesville, but yesterday he explicitly condemned right-wing racist elements.

But in an impromptu media conference at Trump Tower in New York this morning, Mr Trump seemed to undo those comments.

He praised his own controversial initial statement, even pulling it from his suit pocket to read it again.

"The statement I made on Saturday, the first statement, was a fine statement, but you don't make statements that direct unless you know the facts," he said.

"It takes a little while to get the facts."

He then angrily laid blame on liberal groups in addition to white supremacists for the Charlottesville violence.

"They came at each other with clubs … it was a horrible thing to watch," Mr Trump said.

He added that left-wing protesters "came violently attacking the other group".

"There are two sides to a story," he said.

Donald Trump pointed the finger at liberal groups and white supremacists. ( AP: Pablo Martinez Monsivais )

He added that some facts about the violence in Charlottesville still were not known.

A woman was killed when a car ploughed into anti-racism protesters who were confronting white supremacists in the Virginia college town, and dozens more were injured in the violence between the two groups.

Mr Trump came under fire for waiting too long to condemn the white nationalist groups involved in the deadly clashes.

He initially condemned "hatred, bigotry and violence on many sides", but yesterday bowed to mounting political pressure and spoke out against the hate groups involved.

In a statement to reporters at the White House he denounced neo-Nazis, white supremacists and the Ku Klux Klan as "criminals and thugs".

"Racism is evil and those who cause violence in its name are criminals and thugs, including the KKK, neo-Nazis, white supremacists and other hate groups that are repugnant to everything we hold dear as Americans," Mr Trump said.

Rescue personnel help injured people after a car rammed into anti-racism protesters. ( AP: Steve Helber )

Four business leaders have resigned from a presidential advisory panel in protest over Mr Trump's handling of the violence.

They include Merck chief executive Kenneth Frazier, Under Armour chief executive Kevin Plank, Intel chief Brian Krzanich and Alliance for American Manufacturing president Scott Paul.

White nationalist groups march with torches through the UVA campus in Charlottesville, Virginia on Friday night. ( The Indianapolis Star via AP )

Other prominent leaders have also spoken out against Mr Trump's stance.

United States Marine Corps Commandant Robert Neller tweeted after the press conference: "No place for racial hatred or extremism in @USMC. Our core values of Honor, Courage, and Commitment frame the way Marines live and act."

Trump retweets critic who called him a 'fascist'

Meanwhile, Mr Trump has appeared to have mistakenly retweeted a message from one of his critics who said "he's a fascist".

Trump deleted his retweet on Tuesday after about five minutes, but not before the message — sent to his 35 million followers — generated a big response.

Trump seems to have been trying to draw attention to an article on a possible presidential pardon for former Phoenix-area Sheriff Joe Arpaio, who was convicted of a crime for ignoring a US court order to stop traffic patrols targeting immigrants.

A Twitter handle identified as "@MikeHolden42" tweeted to Trump, "He's a fascist, so not unusual."

Loading

The user suggested in subsequent tweets that he was calling Mr Trump a fascist, not Mr Arpaio.

Mr Trump retweeted the message to his massive following, triggering an avalanche of replies.

He later updated his description on Twitter to "Officially Endorsed by the President of the United States".

Trump also retweeted and then deleted a cartoon showing a train labelled "Trump" running over a CNN reporter.

The caption was, "Fake news can't stop the Trump train".

Reuters/AP