Kyle Rittenhouse, who was acquitted over the killing of two men and wounding of another during unrest that followed the shooting of a black man by a white police officer, has said in a new interview that he is not a racist person and supports the Black Lives Matter movement.

"This case has nothing to do with race. It never had anything to do with race. It had to do with the right to self-defence," the 18-year-old told Fox News host Tucker Carlson in an interview to be broadcast on Monday.

Rittenhouse was 17 last year when he travelled 20 miles from his home in Antioch, Illinois, to Kenosha, Wisconsin, which had been racked with protests in the wake of the August 23 shooting of Jacob Blake.

That shooting and the violent response in Kenosha became part of the national reckoning over police use of force against black people following George Floyd's death in Minneapolis the previous May at the hands of police.

Rittenhouse, armed with an AR-style semiautomatic rifle, joined others who said they were intent on protecting private property from potential damage on August 25.

During his trial, prosecutors argued that the teenager as a "wannabe soldier" who went looking for trouble that night.

Rittenhouse said he fired in self-defence after he was attacked and in fear for his life.

Rittenhouse was photographed in a bar before the trial with apparent members of the far-right Proud Boys. Rittenhouse's lawyers have said he is not a white supremacist.

"I'm not a racist person. I support the BLM movement, I support peacefully demonstrating," Rittenhouse tells Carlson in excerpts of the interview released by Fox News ahead of its broadcast.

A jury last Friday found Rittenhouse not guilty on charges of homicide, attempted homicide and reckless endangering over the deaths of Joseph Rosenbaum, 36, and Anthony Huber, 26, and the wounding of Gaige Grosskreutz, now 28.