The request could allow the vaccine – a two-dose series – to be approved by the agency in the coming weeks.
Pfizer and BioNTech's vaccine has already been granted emergency use authorization in children between the ages of 5 and 11.
In addition, children as young as 5 years old who are immunocompromised are also eligible for extra shots.
The Washington Post first reported the move.
On Sunday, former FDA commissioner and Pfizer board member Scott Gottlieb told CBS News that the vaccine might be authorized for the youngest age group as soon as March.
A person familiar with the matter told The Associated Press on Monday that the way for the shots – while awaiting data on a three-dose course, expected in March – could be cleared as soon as this month.
Early Pfizer data has shown the vaccine, administered to children at one-tenth the strength of the adult shot, is safe and produces an immune response.
However, Pfizer announced last year that the two-dose shot proved to be less effective at preventing COVID-19 in kids ages 2-5, prompting regulators to encourage a third shot – administered at least two months after the second dose.
Young children are far less likely than adults to die or develop serious complications from COVID-19.
However, as the omicron variant of the coronavirus has continued to spread across the U.S., hospitalizations in children under 5 with COVID-19 climbed.
The American Academy of Pediatrics said at the end of last month that more than 1.1 million children had been diagnosed with coronavirus in a single week: a 17% increase from the week before.
The organization noted that more than 10.6 million children had tested positive for COVID-19 since the onset of the pandemic, with more than 2 million of those cases added in two weeks of January.
Centers for Disease Control and Prevention Director Dr. Rochelle Walensky warned at the beginning of the month that pediatric hospitalizations were "at their highest rate compared to any prior point in the pandemic," though the agency noted that the numbers include those admitted for other reasons but found to be infected and that the surge could partially be attributable to how hospitalizations in the age group are defined.
Only around 8.7 million children between the ages of 5 and 11 have received at least one dose of the vaccine and 6.2 million are fully vaccinated.
The Associated Press and Fox News' Paul Best contributed to this report.