"Loony lies and conspiracy theories are cancer for the Republican Party and our country," Senate Minority Leader Mitch McConnell said Monday after questions about Rep. Marjorie Taylor Greene, R-Ga.
"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," McConnell said.
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McConnell, R-Ky., did not mention the Georgia representative by name, but his statement was released after NBC News asked about the controversial freshman lawmaker.
"This has nothing to do with the challenges facing American families or the robust debates on substance that can strengthen our party," his statement said.
Greene on Twitter seemed to respond, writing: "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."
She came under scrutiny last week over past remarks, including ones suggesting that school shootings in Newtown, Connecticut, and Parkland, Florida, were staged. Greene has also in the past expressed support for the QAnon conspiracy.
McConnell and Greene, who was elected in November after the Democrat running against her dropped out of the race,are in different chambers, and Monday's comments by McConnell appear to be the first that the Senate minority leader has made on the issue.
The resolution, sponsored by Reps. Debbie Wasserman Schultz and Ted Deutch, both of Florida, and Jahana Hayes of Connecticut, would remove Greene from the House Education & Labor Committee and the House Budget Committee.
The Rules Committee said it would consider the resolution Wednesday, the first step in getting it to a vote on the floor.
House Minority Leader Kevin McCarthy, R-Calif., is expected to speak to Greene this week, but it's unclear if the party will take any action against her.
"These comments are deeply disturbing and Leader McCarthy plans to have a conversation with the Congresswoman about them," a spokesperson for McCarthy told Axios last week.
Republican Rep. Adam Kinzinger of Illinois on Sunday called for Greene to be removed from committees. And Sen. Rob Portman, R-Ohio, also weighed in Sunday, saying on CNN that, "Republican leaders ought to stand up and say it is totally unacceptable what she has said."
The mother of one 2018 Parkland school shooting victims said on MSNBC Sunday that Greene told her that she does not believe major school shootings from the past decade were false flag events or that they had been staged.
But Linda Beigel Schulman, whose son, Scott Beigel, was among the 17 people killed in the mass shooting, said Greene declined to join her to publicly disavow them on MSNBC.
In an interview with OAN on Monday, Greene defended a video that showed her harassing Parkland survivor David Hogg, but appeared to say the shootings "are not fake, and it's terrible the loss that these families go through and their friends as well."
Greene has said she is being attacked in part because of her support for former President Donald Trump.