Foreign Minister Luis Ernesto Derbez said criticism from the United States was a sign of a "a total lack of understanding of our culture" and a "total lack of respect for our culture," El Universal newspaper reported Friday.
White House spokesman Scott McClellan said the types of stereotypes depicted by the stamp are offensive "regardless of their origin."
The stamps in question are of a classic Mexican cartoon named Memin Pinguin, who is drawn with exaggerated features used by old cartoonists to depict black characters.
The Rev. Jesse Jackson called on Mexican leaders this week to "to issue a complete and full apology and to take this stamp off the market immediately." The NAACP said in a statement the stamps were "injurious to black people who live in the United States and Mexico."
Leaders in Mexico defended the stamps against Jackson's accusations saying the character is not interpreted as a racial slur by Mexicans, who in turn don't take offense to the American cartoon character Speedy Gonzalez.
