US Senator Elizabeth Warren released the results of a DNA analysis on Monday that she said indicated she had some Native American heritage – a direct rebuttal to Donald Trump, who has long mocked her ancestral claims and repeatedly referred to her as Pocahontas.

The Massachusetts Democrat and potential 2020 presidential contender challenged Trump to make good on his pledge to donate $1m to charity if she provided proof of Native American heritage, a moment that was caught on video.

When asked by reporters on Monday whether he would make good on his pledge, the US president said he 'didn't say that'.