President Donald Trump targeted Dr. Deborah Birx, a leading member of the White House coronavirus task force, in a tweet Monday, complaining that she "hit us" following reported criticism of her from House Speaker Nancy Pelosi.
Trump said on Twitter that Pelosi, D-Calif., had gone after Birx "because she was too positive on the very good job we are doing on combatting the China Virus, including Vaccines & Therapeutics."
"In order to counter Nancy, Deborah took the bait & hit us. Pathetic!" Trump wrote.
It was not immediately clear which of Birx's remarks Trump was referencing in the tweet. The White House did not respond to CNBC's request for clarification.Â
When asked about his tweet at a White House press briefing Monday evening, Trump said: "I think we're doing very well, I told Dr. Birx I think we're doing very well, she was in my office a little while ago. It's a person I have a lot of respect for. I think Nancy Pelosi's treated her very badly, very, very badly, very nasty."
Trump did not respond when asked to clarify if he disagreed with Birx's characterization of the current state of the pandemic.
Birx had warned on CNN's "State of the Union" on Sunday that the U.S. had entered a "new phase" in its battle against the virus.Â
"What we are seeing today is different from March and April. It is extraordinarily widespread ... it's more widespread and it's both rural and urban," Birx said.Â
Trump's tweet marks a shift in tone toward Birx, the White House's Covid-19 coordinator who had reportedly stayed in good standing with the president throughout much of the pandemic.
Birx's sobering comments came days after Pelosi had slammed her as "the worst," in a closed meeting with White House officials, Politico reported Friday.
"Wow, what horrible hands you're in," Pelosi reportedly said of Birx in the meeting with Treasury Secretary Steven Mnuchin and White House chief of staff Mark Meadows.
On Sunday, Pelosi told ABC News' "This Week" that she does not have confidence in Birx. "I think the president has been spreading disinformation about the virus and she is his appointee, so, I don't have confidence there, no," Pelosi said.
Birx responded to those comments on CNN on Sunday, saying she has "tremendous respect for the speaker, and I have tremendous respect for her long dedication to the American people."
Birx in that interview went on to criticize a New York Times article from last month that portrayed her as pushing an overly optimistic view of the virus' impact in the U.S. "I think it was unfortunate that New York Times wrote this article without speaking to me. I could have brought forth the data," Birx said.
"This was not a Pollyannish view. I have never been called Pollyannish or non-scientific or non-data driven. And I will stake my 40-year career on those fundamental principles of utilizing data to really implement better programs to save more lives."
The Times article said that Birx declined a request to be interviewed.Â
On Monday, Pelosi appeared on CNN and doubled down on her critique of Birx.
"I don't have confidence in anyone who stands there while the president says swallow Lysol and it's going to cure your virus," Pelosi said, referring to Trump's speculation during a White House briefing on the virus months earlier that disinfectants could perhaps be injected as a treatment for Covid-19.