The US is expected to start Covid-19 vaccination this week for children as young as six months old.
The plan came after the US Centers for Disease Control and Prevention (CDC) signed off on the shots for an additional 19 million children across the US, Xinhua news agency reported.
The CDC's advisory panel on Saturday unanimously recommended the Pfizer-BioNTech vaccine for children aged 6 months through four years, as well as the Moderna vaccine for children aged 6 months through five years.
"We know millions of parents and caregivers are eager to get their young children vaccinated, and with today's decision, they can," said CDC Director Rochelle Walensky in a statement.
The CDC's move came a day after the US Food and Drug Administration amended emergency use authorisations for the two vaccines to include the youngest age group.
This was the last age group in the US without access to a Covid-19 vaccine.
Since the pandemic began, more than 13.5 million US children have tested positive for the coronavirus, according to the latest report of the American Academy of Pediatrics and the Children's Hospital Association.
Although Covid-19 is normally less severe in children than adults, the virus can be life threatening for some children. Covid-19 is the fifth leading cause of death for children aged 1 to 4 years from March 1, 2020, to April 30, 2022, according to CDC data released on Friday.
The White House said vaccinations for children aged below 5 years would begin on Tuesday after the Juneteenth federal holiday.
The Joe Biden administration has procured a significant supply of vaccines for this age group, with 10 million doses available initially and millions more available in the coming weeks, according to a plan released by the White House.
Parents will be able to get their youngest children vaccinated at their pediatricians' offices, as well as at pop-up clinics at children's museums, libraries and child-care sites, according to the plan.
Appointment availability might be limited initially but every parent who wants to get their child vaccinated should be able to do so in the next few weeks, said Ashish Jha, who oversees the Biden administration's Covid-19 response.