President Donald Trump responded to Sen. Elizabeth Warren's Monday announcement that she was forming an exploratory committee for a potential 2020 presidential run.

During a phone interview with Fox News contributor Pete Hegseth whether or not Warren can win.

"Well, that I don't know," Trump responded. "You’d have to ask her psychiatrist."

The president also mocked the Democratic senator from Massachusetts, who he has repeatedly called "Pocahontas," because of her claim that she is part-Native American.

President Donald Trump responded to Sen. Elizabeth Warren's Monday announcement that she is forming an exploratory committee for a potential 2020 presidential run.

During a phone interview with Fox News contributor Pete Hegseth asked Trump whether or not Warren can win.

"Well, that I don't know," Trump responded. "You’d have to ask her psychiatrist."

Trump made this comment during an interview for Fox News' "All-American New Year" special that airs on New Year's Eve.

The president also mocked the Democratic senator from Massachusetts, who he has repeatedly called "Pocahontas," because of her claim that she is part-Native American.

"Elizabeth Warren will be the first," Trump said, referring to Warren being the first major Democrat to throw her hat into the ring. "She did very badly in proving that she was of Indian heritage. That didn't work out too well."

In an apparent attempt to get ahead of attacks related to her claim, Warren released a video discussing a DNA test that she took, the results of which she said "strongly support" her claim of Native American ancestry. The response to the October video was mixed — and even elicited a negative response from Native American leaders.

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In a video emailed to supporters on New Year's Eve day, Warren announced she was launching an exploratory committee for a presidential run.

Warren is the first well-known Democrat to announce a potential run in what is expected to be a crowded field for the 2020 Democratic presidential nominee.