Speaking in the White House to Navajo Native American “code talkers”, military veterans who used their indigenous language as a code to pass messages during the Second World War, he said they had been in the country “long before any of us were here”.
“Although we have a representative in Congress who they say was here a long time ago,” he added. “They call her Pocahontas.”
As Mr Trump spoke in the Oval Office, the veterans stared at him. They said nothing and nobody laughed at the President’s supposed joke. He then quickly put his hand on the shoulder of one of the veterans and said: “But you know what - I like you, because you are special."
Mr Trump’s comments were immediately condemned as racist by Ms Warren and others.
“This was supposed to be an event to honour heroes, people who put it all on the line for our country,” she told MSNBC. “It is deeply unfortunate that the president of the United States can’t even make it through a ceremony honouring these heroes without throwing out a racial slur.”
Her fellow Massachusetts senator, Ed Markey, said: “What Mr Trump said about my partner, Senator Warren is a slur. It disparages the Native American war heroes, standing right beside the President, who risked their lives to protect his right to make such a disgusting comment.”
Many pointed out that Mr Trump's words appeared all the more insensitive given that they were made in front of portrait of Andrew Jackson, the seventh US president who forced hundreds of thousands of indigenous people from their land in the 1830s.
Tara Houska, a Native American activist, told The Independent Mr Trump's words were "appalling and disgusting". “Pocohantas was a real person - her name was Matoaka,” she said.
“It’s incredibly disgusting he would make a comment that reduces an entire demographic of Native American women to the name Pocohantas, in front of native men he was supposed to be honouring.”
The White House sought to dismiss the criticism. Asked if the word was racist, White House press secretary Sara Huckabee Sanders, said: “I don't think that it is.”
She was then asked why the President would say something that was “offensive to many people while honouring the Navajo code talkers - genuine American heroes”.
She responded: “I think what most people find offensive is Senator Warren lying about her heritage to advance her career.”
Earlier, Peter MacDonald, a Second Wold War veteran and former chairman of the Navajo tribe, gave introductory remarks by going through the history of the code talkers in the Pacific military theatre, including at the battles at Guadalcanal and Iwo Jima. Their vital contribution was featured in the 2002 film Windtalkers, starring Nicolas Cage and Adam Beach.
Mr Trump’s chief of staff, former general John Kelly, spoke of the role the men had played in helping secure victory in places such as Iwo Jima.
“What these men did was one of the very factors that allowed us to be successful on that island,” said Mr Kelly.
During the 2016 election campaign, Mr Trump frequently used the word “Pocahontas” in reference to Ms Warren the Massachusetts senator, who has said she has Native American ancestry.
“I am very proud of my heritage,” Ms Warren told an interviewer in 2012. “These are my family stories. This is what my brothers and I were told by my mom and my dad, my mamaw and my papaw. This is our lives. And I’m very proud of it.”
Mr Trump used the word to mock someone who has been one of his most outspoken critics. He even claimed he had invented her claimed heritage.
“She made up her heritage, which I think is racist. I think she's a racist, actually because what she did was very racist,” he said.
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