WASHINGTON (NewsNation Now) — Wyoming Rep. Liz Cheney Monday hit back at former President Donald Trump’s unfounded claims that the 2020 election was stolen.

Trump issued a statement Monday morning saying, “The Fraudulent Presidential Election of 2020 will be, from this day forth, known as THE BIG LIE!”

“The 2020 presidential election was not stolen,” Cheney said on Twitter hours after Trump’s statement. “Anyone who claims it was is spreading THE BIG LIE, turning their back on the rule of law, and poisoning our democratic system.”

Trump’s claims that the election was stolen have never been proven.

Cheney, the No. 3 Republican in the House of Representative, was one of 10 Republicans who voted to impeach Trump. Cheney quickly faced an effort by conservatives to remove her from her leadership post. She survived it, but Trump has vowed to throw his support behind a primary challenger to her.

Just six months after winning a third term with almost 70%, Cheney already faces at least two Republican primary opponents in 2022.

The Wyoming Republican Party voted overwhelmingly to censure Cheney. The censure document accused Cheney of voting to impeach Trump, even though the House didn’t offer him a “formal hearing or due process.”

In a statement after the vote, Cheney said she remained honored to represent Wyoming and will always fight for issues that matter most to the state.

“People have been lied to,” Cheney said in February. “The extent to which the president, President Trump, for months leading up to Jan. 6 spread the notion that the election had been stolen or that the election was rigged was a lie.”

Cheney, the daughter of former Vice President Dick Cheney and a fixture of the party establishment, blasted her state party for the censure, noting that state Republicans embraced conspiracy theories such as the inaccurate claim non-Trump supporters were behind the violent protests.

The Associated Press and Reuters contributed to this report.