During a ceremony honoring Navajo “code talker” veterans of World War II, President Donald Trump couldn’t resist repeating one of his favorite racist insults towards Democratic Senator Elizabeth Warren — a comment that didn’t go over well with Indigenous leaders.

Trump called Warren “Pocahontas” during the Monday ceremony, referring to her claim of Native American heritage.

“You were here long before any of us were here. Although we have a representative in Congress who they say was here a long time ago. They call her Pocahontas,” Trump said to the veterans, who are now in their 90’s. They did not seem to respond to the comment, either because they were not amused or Trump’s war of words against Warren was lost on them.

The White House said Trump’s remark was not a racial slur and deflected questions about it by bringing up Warren’s claim and calling it false. But not everyone was going to let the comment slide.

In addition to drawing outrage on social media, Trump’s comments drew the ire of Indigenous leaders from around the country.

John Norwood, general secretary of the Alliance of Colonial Era Tribes, said Trump’s nickname for Warren “smacks of racism.”

“The reference is using a historic American Indian figure as a derogatory insult and that’s insulting to all American Indians,” said John Norwood, the general secretary of the Alliance of Colonial Era Tribes, adding that the comment “smacks of racism.”

Norwood told MSNBC that the president should “stop using our historical people of significance as a racial slur against one of his opponents.”

Native Peoples activist Faith Spotted Eagle of the Yankton Sioux told the Toronto Star that Trump’s use of “Pocahontas” is an “emotional assault” that “carries as much weight as a physical assault.”

“He can phrase it and twist it and distort it any way he wants, the fact remains: that name does not belong in his mouth,” Spotted Eagle told the Star’s Daniel Dale.

This isn’t the first time Indigenous groups have condemned Trump’s use of “Pocahontas” in reference to Warren.

“With the election long over, we hoped that President Trump would refrain from using this name as a pejorative term and other such terms that insult Native peoples and degrade their cultures in order to score political points,” said National Congress of American Indians President Brian Cladoosby in May. “We hope that this was but a momentary slip-up, and that it is not indicative of how this Administration intends to treat and work with Indian Country moving forward.”