GOP presidential front-runner Donald TrumpDonald John TrumpMia Love pulls ahead in Utah race as judge dismisses her lawsuit Trump administration denies exploring extradition of Erdoğan foe for Turkey Trump congratulates Kemp, says Abrams will have 'terrific political future' MORE on Monday called Sen. Elizabeth WarrenElizabeth Ann WarrenElection Countdown: Abrams ends fight in Georgia governor's race | Latest on Florida recount | Booker, Harris head to campaign in Mississippi Senate runoff | Why the tax law failed to save the GOP majority Entrepreneur touts big solutions, endorsements in discussing presidential bid Warren, 2020 Dems target private immigration detention center operators MORE (D-Mass.) an “Indian,” mocking her for an old claim of Native-American ancestry.

Earlier in the day, Warren went on a Twitter rant against Trump, calling him a "loser" and a "serious threat" to the United States.

“You mean the Indian?” Trump asked when a reporter inquired about the senator's comments during a press conference in Washington, D.C. “Who’s that? The Indian?”

ADVERTISEMENT

Trump accused Warren of inflaming tensions between everyday Americans by attacking the legitimacy of his White House run.

“The problem with this country right now is it’s so divided,” he said. "People like Elizabeth Warren really have to get their act together because it’s going to stay divided."

“That includes Hillary,” Trump continued. "And that probably includes me."

Warren met with controversy during her 2012 Senate campaign when reports emerged that Harvard Law School once touted her alleged Cherokee and Delaware ancestors as proof of its faculty’s diversity.