Sen. Elizabeth Warren, D-Mass., is calling on President Trump to donate the $1 million he promised to charity if she proved she has Native American heritage.

Warren reminded the president in a tweet Monday that he said at a rally in Montana in July he would donate to a charity of Warren’s choosing if she took a DNA test to prove her ancestry.

“Remember saying on 7/5 that you’d give $1M to a charity of my choice if my DNA showed Native American ancestry? I remember — and here’s the verdict. Please send the check to the National Indigenous Women’s Resource Center,” she wrote.

Warren announced the results of her DNA test early Monday, showing “strong evidence” that she had Native American ancestry.

Trump has repeatedly mocked Warren over her ancestry claims. Speaking to reporters on Monday, Trump denied saying he would donate $1 million if Warren proved her claims.

“Who cares?” Trump said. “I didn’t say that. You better read it again.”