During an event honoring Native American veterans, President Donald Trump referred to Senator Elizabeth Warren as "Pocahontas."
Trump welcomed three Navajo code talkers from World War II to the Oval Office. He called them "incredible" and "very special people."
And then he added: "We have a representative in Congress who they say was here a long time ago. They call her Pocahontas. But you know what, I like you."
Trump has repeatedly mocked Warren for claims she has made about being part Native American.
Native American leaders have called Trump's past attacks on Warren offensive and distasteful.
Warren quickly denounced Trump's comments.
"This was supposed to be an event to honor heroes, people who put it all on the line for our country, who, because of their incredible work, saved the lives of countless Americans and our allies," Warren said in an interview on MSNBC. "It is deeply unfortunate that the president of the United States cannot even make it through a ceremony honoring these heroes without having to throw out a racial slur."
The Associated Press contributed to this report.