(CNN) A day after President Donald Trump privately excoriated the US Centers for Disease Control and Prevention to Republican senators during a lunch on Capitol Hill, the fate of the agency's director, Dr. Robert Redfield, is in question.
Trump did not bring up or single out Redfield during his lunch with GOP senators, multiple sources familiar with the discussion told CNN. The director was also at the White House on Monday for a meeting.
The President said Wednesday that Redfield is doing a "very good job" leading the agency and denied ever discussing the CDC at Tuesday's lunch on Capitol Hill with GOP senators.
"I think he's done a very good job. I think my whole team has done a very good job," Trump said, adding that there is "great talent" at the CDC.
As recently as last week, Redfield told colleagues he didn't think he was in trouble or that his job was on the line. According to a senior administration official, Redfield expressed confidence that the current tension with White House coronavirus task force coordinator Dr. Deborah Birx, who Redfield has a decades long relationship with, was fleeting.
Over the weekend, the momentum appeared to have shifted. Redfield grew concerned he may have a target on his back, according to a source familiar with the dynamic. CDC officials dismissed the claims that Redfield was in the hot seat.
"Dr. Redfield is going about his job and his interaction with the White House has not changed," one CDC official said, adding that the director had been attending White House meetings on a regular basis.
But one senior administration official told CNN the director's fear is not unfounded.
Informal conversations around "what to do" about Redfield have taken place, as tensions between the CDC and the White House show no signs of abating, according to a senior administration official.
Birx has become increasingly critical of the CDC, making clear in recent meetings that she is more than frustrated with the agency, according to two senior administration officials. Specifically, Birx believes the way the CDC gathers data on the coronavirus is antiquated, causing inaccurate and delayed numbers on both virus cases and deaths. Birx has expressed her agitation during recent task force meetings, where at least one conversation between her and Redfield has grown heated, according to a source close to the task force.
This comes after an interview Sunday, where White House trade adviser Peter Navarro publicly blamed the CDC for the testing failures in the United States. Navarro argued that the top health agency, under Redfield, "let the country down" on testing.
Two senior administration officials told CNN Navarro was just expressing the frustration that many in the administration felt, including the President himself, toward the CDC. After Navarro's comments blew up and Health and Human Services Secretary Alex Azar called them "inaccurate and inappropriate."
Navarro later expressed concerns to some colleagues that he had gone too far, but was assured by administration officials that he had not -- and that Trump would not be speaking up to defend the CDC.
On Wednesday, Trump said he was "not blaming CDC" for "something going wrong with one of the tests" in the study.
One official has pushed back on the idea that Redfield was in immediate trouble, saying there isn't an appetite within the administration for any seismic staffing changes while the response to coronavirus was ongoing. However, this official said that ultimately the decision was up to Trump.
During Tuesday's Republican Senate lunch, the President praised his son-in-law and top adviser Jared Kushner and his team as having solved the testing problem in the US he claimed was botched by the CDC.
A senior CDC official responded to the President's criticism by pointing to the death toll -- at more than 90,000 -- and asking how criticizing the agency helps anything at this stage.
"I would urge the President to understand that to prevent spread we must focus on containment and mitigation. He wants to focus on criticism. We will focus on the science, as we have done from the beginning," the official told CNN.
But according to sources working closely with the White House on the coronavirus response, the CDC and Redfield have been nearly impossible to reach. Officials at the CDC deny this.
Even when trying to present the agency with helpful data or get guidance on various aspects of reopening, these sources said the only way to get what they needed was to go around the organization, and described Vice President Mike Pence and Birx as easier to reach and more responsive than Redfield or anyone at the CDC.
Redfield has also been missing from key conversations about how to advance the CDC's data collecting methods. The agency has been working around the clock, holding meetings and conference calls with federal officials and members of the private sector to implement a major data modernization initiative.
While a team of CDC employees has been involved in the process, the initiative has lead by Birx, not Redfield, sources familiar with these conversations told CNN.
"She's clearly the one in charge," one source familiar told CNN.
CNN's Kaitlan Collins and Nick Valencia contributed to this report.