Britain will see a significant reduction in the number of vaccines available from March 29 due to a cut in supply, a letter sent around the state-run health service said on Wednesday.
Britain has rolled out the fastest vaccine programme of any large country but it has also clashed repeatedly with Brussels over supplies.
The European Union threatened on Wednesday to ban exports of COVID-19 vaccines to Britain to safeguard scarce doses for its own citizens as it aired frustration over a lack of deliveries coming from AstraZeneca in Britain.
"The Government's Vaccines Task Force has now notified us there will be a significant reduction in weekly supply available from manufacturers beginning in the week commencing 29 March, meaning volumes for first doses will be significantly constrained," the letter said.
"They now currently predict this will continue for a four-week period, as a result of reductions in national inbound vaccines supply."
Britain says it is on track to have given a first COVID-19 shot to half of all adults in the next few days and it said earlier on Wednesday that more than 25 million people had now received the first vaccination.
The letter to the NHS said for the four-week period it would focus on making sure all those in the most vulnerable categories received their first shot, while those who have received their first vaccine receive their second on time.
{{/usCountry}}The letter to the NHS said for the four-week period it would focus on making sure all those in the most vulnerable categories received their first shot, while those who have received their first vaccine receive their second on time.
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