US Senate Republican Mitch McConnel on Monday, reportedly launched a scathing criticism on one of his party members, assailing congresswoman Marjorie Taylor Greene as a “cancer” to the Republican party, reported AFP.

Greene has supported debunked conspiracy theories by far-right group QAnon and echoed former president Donald Trump‘s baseless claims of rigging in the 2020 election. She is now facing mounting anger over her rhetoric.

McConnell, in a statement to The Hill, warned that the first-term Georgia lawmaker’s embrace of “loony lies and conspiracy theories” is a “cancer for the Republican Party” that is already deeply divided over its path forward in the post-Trump era.

He said, “Somebody who’s suggested that perhaps no airplane hit the Pentagon on 9/11, that horrifying school shootings were pre-staged, and that the Clintons crashed JFK Jr.’s airplane is not living in reality.”

Greene is facing huge backlash after she posted a video of herself harassing a school shooting survivor and “liking” posts about executing leading Democrats including House Speaker Nancy Pelosi.

According to McConnell, Greene’s rhetoric “has nothing to do with the challenges facing American families or the robust debates on substance that can strengthen our party.”

Responding to the jibes, Greene said on Twitter, “The real cancer for the Republican Party is weak Republicans who only know how to lose gracefully. This is why we are losing our country.”

McConnell, a Trump ally who broke with the outgoing president in December over his repeated insistence that the election was stolen from him, did not mention Greene by name in his statement, according to The Hill.

But the fierce denunciation by the leading Republican in the upper chamber in Congress suggests McConnell is acutely aware of the potential damage she could inflict on the party as it mounts an effort to retake the House and Senate in the 2022 midterm elections.

Greene claims she enjoys support from Trump, and said Saturday that the two spoke by telephone. She also stressed she will “never apologize” as she faces a backlash over her remarks and actions.

House Minority Leader Kevin McCarthy is expected to meet with Greene this week as pressure mounts on him to take action.

Democrats are threatening to hold a floor vote this week to oust Greene from the House Education and Labor Committee and the Budget Committee if McCarthy does not remove her.