Sen. Elizabeth Warren Elizabeth WarrenHarris joins women's voter mobilization event also featuring Pelosi, Gloria Steinem, Jane Fonda Judd Gregg: The Kamala threat — the Californiaization of America GOP set to release controversial Biden report MORE (D-Mass), a 2020 Democratic presidential hopeful, on Sunday said that Trump administration officials have a constitutional duty to invoke the 25th Amendment if they believe the president cannot fulfill his job, saying their loyalty should be to "the Constitution" and not to the president.

“My point here is that if they believe that Donald Trump Donald John TrumpOmar fires back at Trump over rally remarks: 'This is my country' Pelosi: Trump hurrying to fill SCOTUS seat so he can repeal ObamaCare Trump mocks Biden appearance, mask use ahead of first debate MORE cannot fulfill the obligations of his office, then they have a constitutional responsibility to invoke the 25th Amendment,” Warren said during a news conference after a rally in Las Vegas, according to The Nevada Independent.

“Their loyalty under law is not to him personally. It is to the Constitution of the United States and to the people of United States.”

The comments from Warren came days after CBS aired a segment of an interview with former FBI Deputy Director Andrew McCabe Andrew George McCabeGraham: Comey to testify about FBI's Russia probe, Mueller declined invitation Barr criticizes DOJ in speech declaring all agency power 'is invested in the attorney general' GOP votes to authorize subpoenas, depositions in Obama-era probe MORE in which he said top Justice Department officials discussed launching an effort to invoke the 25th Amendment to force Trump out of office following former FBI Director James Comey's firing in May 2017.

He also said Deputy Attorney Generalhad offered to wear a wire around the president.

A spokesperson for McCabe walked back the remarks last week, saying that the former FBI official did not "participate in any extended discussions about the use of the 25th Amendment, nor is he aware of any such discussions."

The Justice Department also issued a statement reiterating Rosenstein's denial of his offer to wear a wire, which Rosenstein called "inaccurate and factually incorrect."

Sen. Lindsey Graham Lindsey Olin GrahamSenate GOP aims to confirm Trump court pick by Oct. 29: report The Hill's Campaign Report: GOP set to ask SCOTUS to limit mail-in voting Senate GOP sees early Supreme Court vote as political booster shot MORE (R-S.C.) on Sunday vowed to "get to the bottom" of the alleged Justice Department discussions about the 25th Amendment.

"It's stunning to me that one of the chief law enforcement officers of the land, the acting head of the FBI, would go on national television and say 'Oh by the way, I remember a conversation with the deputy attorney general about trying to find if we could replace the president under the 25th amendment,' " Graham said on CBS's "Face The Nation."

"We're a democracy. People enforce the law. They can't take it into their own hands. And was this an attempted bureaucratic coup?"

Warren, a frequent Trump critic, said in a speech in Iowa last week that "by the time we get to 2020, Donald Trump may not even be president."

Trump has repeatedly derided Warren during his time in office, often referring to her as "Pocahontas" while taking aim at her past claims of Native American heritage.