The Food and Drug Administration on Friday approved emergency use of the Moderna and Pfizer-BioNTech COVID-19vaccines for children as young as 6 months old.

The news comes two days after an expert panel at the FDA gave its approval for emergency use in small children. The Centers for Disease Control and Prevention must still give its OK before those kids can start getting their shots, which could happen as early as next week.

In giving its approval, the FDA said that its analysis of the safety and effectiveness of the vaccines was "rigorous and comprehensive" and that it determined that the benefits of both vaccines outweighed their potential risks.

"As we have seen with older age groups, we expect that the vaccines for younger children will provide protection from the most severe outcomes of COVID-19, such as hospitalization and death," FDA Commissioner Dr. Robert Califf said in a statement.

Pfizer's vaccines had previously been approved for use in children at least 5 years old, while the Moderna vaccine had only been approved for use in people ages 18 and up.

For most small children, the Moderna vaccines will be administered in two shots one month apart, though some kids with certain kinds of immunocompromise could receive a third shot at least one month after they get their second, the FDA says.

With the Pfizer vaccine, all kids ages 6 months through 4 years will get three shots, the first two of them three weeks apart, followed by a third dose at least eight weeks later.

The White House has said that the vaccinations could start as early as Tuesday, though vaccine availability could vary state to state.