President Barack Obama says work remains on improving relations between police and communities of color in the United States.

“Over the past year, we’ve come to see, more clearly than ever, the frustration in many communities of color and the feeling that our laws can be applied unevenly,” Obama said Saturday during his weekly address.

Many US cities have been the scene of mass protests since last summer, when unarmed black teenager Michael Brown was shot and killed by a white police officer in Ferguson, Missouri.

The US must deal “honestly with issues of race, poverty, and class that leave too many communities feeling isolated and segregated from greater opportunity,” Obama said.

Brown’s death, and the subsequent acquittal of Darren Wilson, has amplified the national debate about racial inequality and police brutality in the United States.

Fresh violence erupted in Ferguson last week on the anniversary of Brown’s death.

Obama said he has convened a task force of police officers, activists and academics to "build up trust and cooperation between communities and police."

“We've brought together leaders from across the country to explore alternatives to incarceration,” he said. “The Justice Department has begun pilot programs to help police use body cameras and collect data on the use of force.”

Obama, however, acknowledged that the questionable deaths of African Americans by police in Ferguson, New York, Cleveland, Baltimore and other cities will not be solved by policing alone.

He added that communities of color “simply can’t ask ... police to contain and control issues that the rest of us aren't willing to address — as a society.”

America needs to improve its early education to prevent an increase in national crime, the president said.

“More broadly, we need to truly invest in our children and our communities so that many young people see a better path for their lives,” he said. “That means investing in early childhood education, job training, pathways to college.”

A new report by The Washington Post has indicated that US police have shot dead more than 600 people across the country so far this year.