People aged 38 to 39 in England will be able to book Covid-19 vaccinations from Thursday morning.
NHS sources told the PA news agency that the vaccine rollout will continue to younger age groups, with the aim of giving all adults at least once dose by the end of July.
People under 40 are being offered an alternative to the Oxford/AstraZeneca jab, such as the Pfizer or Moderna vaccines.
This is due to the link between the AstraZeneca jab and extremely rare blood clots, including some affecting the brain.
As of Tuesday, 35.6 million first doses of Covid-19 vaccines have been given in the UK, with a further 18 million second doses.
More details on booking vaccinations are expected later on Wednesday.
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