More than 220,000 children in England have already had a Covid-19 vaccine, figures show.
Across the nation 223,755 under-18s have received a first dose, according to NHS data to July 25.
The figures come as it emerged that the offer of a vaccine is expected to be extended to include all 16 and 17 year olds.
In June, vaccines minister Nadhim Zahawi announced that a number of under-18s would be eligible for the jab if they had certain health conditions, lived with someone who is immunocompromised, or were approaching their 18th birthday.
Watch: UK teens aged 16 and 17 expected to be offered Covid vaccine
He said at the time that the vaccine experts who advise the Government, the Joint Committee on Vaccination and Immunisation (JCVI), did not currently recommend that children should be routinely given the jab, but that the matter was being kept under constant review.
However, the PA news agency has learned that some clinics have already begun vaccinating 16-year-olds at walk-up appointments, provided that they attend with their parent or guardian.
NHS data shows that 79,616 children have had both doses.
The Pfizer/BioNTech Covid-19 has been approved for use in children aged 12 to 17.
There has been debate about offering vaccines to children, with some experts saying children should be able to get the jab to prevent further disruption to schooling.
Others have said that it would be morally ambiguous to give the vaccine to children – who are at low risk of serious illness from Covid-19 – when there are serious gaps in vaccine equity around the globe.
Some experts have also suggested that vaccinating children would, in large, not be for their own benefit but to protect those around them.
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