GENEVA (Reuters) - United Nations human rights experts called on U.S. political leaders “at all levels” on Wednesday to combat rising racist violence and xenophobia and urged prosecution of perpetrators of hate crimes.

Women sit by an impromptu memorial of flowers commemorating the victims at the scene of the car attack on a group of counter-protesters during the "Unite the Right" rally as people continue to react to the weekend violence in Charlottesville, Virginia. REUTERS/Justin Ide

U.S. President Donald Trump insisted on Tuesday that both left- and right-wing extremists had become violent during a weekend rally by white nationalists in Virginia, reigniting a political firestorm over race relations in the United States and his own leadership of a national crisis.

After clashes between the two sides at Saturday’s rally, a car ploughed into opponents of the gathering, killing one woman and injuring 19 others. A 20-year-old Ohio man, James Fields, said to have harbored Nazi sympathies, was charged with murder.

“We are outraged by the violence in Charlottesville and the racial hatred displayed by right-wing extremists, white supremacists and neo-Nazi groups,” the independent U.N. experts said in a joint statement issued in Geneva.

“We call for the prosecution and adequate punishment of all perpetrators and the prompt establishment of an independent investigation into the events,” they said.

The legacy of slavery in America has left two “invidious” aspects, the “ongoing racial discrimination” and the notion of white supremacy, said Anastasia Crickley, chair of the U.N. Committee on the Elimination of Racial Discrimination, who is one of the three experts who issued the statement.

“This notion of white supremacy as far as many of us can see is being re-articulated from top to bottom in the USA at the moment,” she told Reuters.

“In looking to addressing racial discrimination, we have got to look to very clear, unequivocal statements from political leaders at all levels,” she added.

Crickley, asked whether Trump was providing leadership on the issue and whether she had concerns on his public statements, replied: “Already leaders across the political spectrum are calling for more political leadership from the White House and from the leadership spectrum. I think yes we do need that.”

The events in Virginia were the “latest examples” of increasing racism, racial discrimination, Afrophobia, racist violence and xenophobia “observed in demonstrations across the USA”, the U.N. experts said.

Recent incidents in California, Oregon, New Orleans and Kentucky had demonstrated “the geographical spread of the problem”, they added.

The statement was also issued by Sabelo Gumedze, chair of the U.N. working group of experts on people of African descent, and Mutuma Ruteere, U.N. special rapporteur on contemporary forms of racism.