A decision to vaccinate all 12 to 17-year-old children against Covid is unlikely to be recommended by UK vaccine experts imminently, the BBC has been told.
Certain groups of children may still be offered a Covid jab - but not all.
But the JCVI - the committee of UK vaccine experts which advises the government on the best approach - has not yet made any formal recommendation on the matter.
The committee may be waiting for more safety data on children who have been vaccinated in other countries, such as the US and Israel, before making its decision.
At the same time, the UK's stock of Pfizer and Moderna vaccines is being prioritised for adults aged 18 to 40 - who are not being offered AstraZeneca - meaning supplies available for children are currently low.
However, for the experts there are a whole host of factors to consider, including the benefits and risks for children, as well as other wider ethical issues.
Some people question whether it's morally right to vaccinate children in the UK, when so many millions of other people in the rest of the world are still unvaccinated.
On the other hand, vaccinating children could reduce infections across society, help protect adults and the vulnerable who are most at risk, and keep schools open.
He said he was "veering towards not vaccinating children" because of the need to get the vaccine into the arms of more hard-to-reach adults instead.
Vaccinating children would be "mainly to protect public health and reduce transmission", he added.
There are concerns there are not enough Pfizer or Moderna vaccines to start vaccinating younger age groups any earlier.
Should all children get a Covid vaccine?