Washington (CNN) Sen. Elizabeth Warren says President Donald Trump's reference to his nickname for her -- "Pochahontas" -- at an event honoring Navajo veterans Monday was just a distraction from other issues.

"He'd sure like to talk about something else," the Massachusetts Democrat said Monday night in an interview with CNN's Anderson Cooper.

"I just want to thank you because you are very, very special people. You were here long before any of us were here," Trump said. "Although, we have a representative in Congress who has been here a long time ... longer than you -- they call her Pocahontas!"

Warren said she "really couldn't believe" Trump's comment.

"There he was, at a ceremony to honor Native Americans, men who have really put it all on the line to save American lives, to save lives of people, our allies, during World War II, really amazing people. And President Trump couldn't even make it through a ceremony to honor these men without throwing in a racial slur," Warren told Cooper on "Anderson Cooper 360."

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