AUSTIN (KXAN) — The COVID-19 vaccine may not become available to children younger than 12 in time for the start of the new school year, a White House health expert said Monday.

Dr. Bechara Choucair, the White House vaccinations coordinator, told KXAN that the necessary federal entities won’t approve the use of vaccines in younger children until “possibly by the end of the year or early 2022.”

“For kids younger than 12 years of age, we know there are studies going on right now for Pfizer, for Moderna and for others, and we’re tracking those,” Dr. Choucair said. “The colleagues at the NIH and the FDA and the CDC will be reviewing those. Once we get the result of those data, the result of those trials, when we start seeing the data and they get evaluated by our scientists and HHS, that’s when we will know we’ll be able to have vaccines available for younger than 12 years of age.”

When pressed about whether he holds out hope that the approval process could happen sooner, Dr. Choucair would only say, “We’re going to have to wait and see.”

“The [Food and Drug Administration] does what the FDA does: review the data, analyze the data and make scientific-based recommendations,” he said. “Once they tell us they’re ready, we’ll all be ready to execute the programs to get people vaccinated who are younger than 12.”

The Pfizer vaccine is currently available for use in people 12 and older. The FDA announced in May that the two-dose shot has now been authorized for emergency use in adolescents 12 to 15 years old.

Last month Moderna also shared its COVID-19 vaccine strongly protects kids as young as 12, which is a step that could put the shot on track to become the second option for that age group in the U.S. However, the FDA has yet to extend that emergency use authorization for younger people.