White House Chief of Staff Mark Meadows has summoned FDA commissioner Stephen Hahn to the West Wing for a 9:30am meeting Tuesday to explain why he hasn't moved faster to approve the Pfizer coronavirus vaccine, two senior administration officials told Axios.

Why it matters: The meeting is shaping up to be tense, with Hahn using what the White House will likely view as kamikaze language in a preemptive statement to Axios: "Let me be clear — our career scientists have to make the decision and they will take the time that’s needed to make the right call on this important decision."

What they're saying: A senior administration official said that in mid-November, Hahn spent a week vacationing in the Outer Banks of North Carolina, and the official expected this subject would be discussed.

• "There are some who are complaining the FDA is not working around the clock to get things approved and because of that, Meadows has asked Dr. Hahn for a briefing," a second administration official said.

Behind the scenes: The first official said Meadows wanted Hahn to explain why he was hearing that the FDA was not moving fast enough to greenlight the Pfizer vaccine, which was the first to be submitted for emergency agency approval.

• An FDA spokesperson denied Hahn was vacationing and responded: "On the point about Dr. Hahn’s recent remote work schedule, Dr. Hahn was recently exposed to COVID while working at the FDA’s White Oak campus. Dr. Hahn chose a remote location to quarantine and he continued working, as he has done throughout the pandemic. Dr. Hahn has worked every single day of this pandemic, including weekends, holidays and more."
• When Meadows requested the meeting, Hahn said he wanted to do it over the telephone. Meadows insisted it be in person.

The other side: When Axios gave the FDA visibility of this reporting and an opportunity to comment, Hahn responded, "We want to move quickly because this is a national emergency, but we will make sure that our scientists take the time they need to make an appropriate decision. It is our job to get this right and make the correct decision regarding vaccine safety and efficacy."

• An agency spokesperson tells Axios, "The amount of data submitted to the FDA includes thousands of pages of technical information that must be divided up and reviewed by experts from different disciplines. Once the reviews by the various experts are completed, they are then integrated into an overall review.
• "Completion of these reviews involves such things as ensuring that the manufacturing process and the controls on manufacturing are appropriate, checking statistical analyses performed to ensure that they were done properly and doing additional analyses, as necessary, to look at the effect of the vaccine on subsets of individuals who might be at greater risk of adverse effects."

Flashback: Trump piled pressure on the FDA to approve a vaccine before the election and baselessly accused the agency of slow-walking approvals to harm his electoral chances.