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 on Thursday criticized as “toxic propaganda” the “1619 Project,” a Pulitzer Prize-winning public school curriculum developed by the New York Times that orients American history from the date that the first slave ship arrived in what later became the U.S.

Earlier this month, Trump tweeted that the Department of Education would cut off federal funding to California schools if they adopted the 1619 curriculum.

The president announced during his speech -- part of the first-ever White House Conference on American History -- that he would include a statue of Declaration of Independence signatory Caesar Rodney in his planned “National Garden of American Heroes.”.

Trump and other top administration officials have said they don’t believe that systemic racism exists, and have argued that curricula like the 1619 Project provide an unduly dark vision of America’s founding.

“We understand Black Studies to be a capacious intellectual project that spans a variety of methodological approaches, fields, geographical areas, languages, and time periods,” the English Department said on its website