Former United States president Jimmy Carter says a lot of the abuse of President Barack Obama over his healthcare and fiscal reforms is "based on racism".
Mr Carter told a meeting there is an inherent feeling among many in the US "that an African-American should not be president".
A Republican lawmaker, Joe Wilson, was reprimanded on Tuesday in a House vote for shouting "You lie!" while Mr Obama was addressing Congress on healthcare.
Mr Wilson's eldest son, Alan, has denied racism was a factor in his father's outburst. But Mr Carter says there is more to the heckling than meets the eye.
The BBC reports that many Americans have not just protested against the President's policies, but have accused him of tyranny, and vowed to "reclaim America".
"Those kind of things are not just casual outcomes of a sincere debate on whether we should have a national programme on healthcare," Mr Carter said at a public meeting at the Carter Center in Atlanta. "It's deeper than that."
White House spokesperson Robert Gibbs says Mr Obama does not believe he is being criticised because of his race.