U.S. President Donald Trump on Thursday denounced school curricula that emphasize the impact of slavery and racism on American history and blamed "left-wing indoctrination” for nationwide protests against police brutality.

"Patriotic moms and dads are going to demand that their children are no longer fed hateful lies about this country,” Trump said in a speech at the National Archives in Washington.

The president claimed U.S. schoolchildren are taught that the U.S. was "founded on the principle of oppression, not freedom” and that they should "feel ashamed of their own history,” a curriculum he called "radical.”