President Donald Trump said he won’t make good on a bet on Senator Elizabeth Warren’s Native American heritage unless he can personally test her DNA.

The Massachusetts lawmaker released results of a genetic test to the Boston Globe on Monday showing she has a distant Native American ancestor. Trump has frequently ridiculed her claim of native heritage, calling her “Pocahontas” — a name that she and some Native Americans have said is a slur.

At a political rally July 5, Trump told his audience that he’d pay $1 million to the charity of Warren’s choice if a DNA test proved she had native blood. Trump on Monday declined to apologize and said Warren “owes the country an apology.”

“What’s the percentage, 1/1000th?” Trump told reporters as he surveyed hurricane damage in Georgia. “I’ll only do it if I can test her personally. And that will not be something I enjoy doing, either.”

Warren’s test showed her native ancestor appeared in her lineage six to 10 generations back, making her less than 2 percent Native American. She has been criticized by Republicans for claiming to be a minority while a legal scholar.

The Cherokee Nation on Monday criticized Warren for claiming a link to Native Americans based on a DNA test.

“Current DNA tests do not even distinguish whether a person’s ancestors were indigenous to North or South America,” Cherokee Nation Secretary of State Chuck Hoskin Jr. said in a statement. “It makes a mockery out of DNA tests and its legitimate uses while also dishonoring legitimate tribal governments and their citizens, whose ancestors are well documented and whose heritage is proven. Senator Warren is undermining tribal interests with her continued claims of tribal heritage.”

Warren, considered a likely contender for the 2020 Democratic presidential nomination, said in a video explaining the test that she does not claim membership in any specific tribe and acknowledged that only tribes determine their citizenship.

“Trump can say whatever he wants about me, but mocking Native Americans or any group in order to try and get at me? That’s not what America stands for,” she said.

Warren told Trump earlier on Monday to send a check to a charity for Native American women.

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