The NHS has been told “there will be a significant reduction” in vaccine supply from the end of March, according to a leaked letter.
The letter from NHS chiefs also tells local health leaders "vaccination centres and community pharmacy-led local vaccination services should close unfilled bookings from the week commencing 29 March" and ensure no further appointments are uploaded to booking systems in April.
During a Downing Street press briefing on Wednesday, health secretary Matt Hancock admitted vaccine supply was "lumpy" but insisted the government was on course to give the first jab to the top 9 priority groups by mid-April and all adults by the end of July.
When asked about the letter, he said: “What you’re referring to is a standard one of those letters, but I’ve set out the details in terms of how we can deliver on the vaccine programme, where we’re on track to meet the target of offering to all groups 1 to 9 on 15 April.”
Hancock added: "If you think about it, it’s currently the middle of March and we’ve already been able to invite all over-50s in and we need to make sure we reach just as high proportion as possible.
"You’ll see in the letter, it refers to the focus that’s needed on the particularly vulnerable groups, so that’s what we’re going to be doing to protect as many people as possible."
The warning of a shortage comes after vaccines minister Nadhim Zahawi said last week there would be a “rapid increase” in the number of people who will receive their first COVID jab before the end of March.
He said there would be a “big uplift” in supply in coming weeks, which would see a surge in people receiving their first dose and many of the highest risk getting their second jab.
But the letter from NHS England leaders states: “The Government’s Vaccines Task Force have now notified us that there will be a significant reduction in weekly supply available from manufacturers beginning in the week commencing March 29, meaning volumes for first doses will be significantly constrained.
“They now currently predict this will continue for a four-week period, as a result of reductions in national inbound vaccines supply.”
New figures showed that almost half of British adults have received a jab in the first 100 days of the vaccination programme.
The Department of Health and Social Care (DHSC) said more than 25 million people have received their first vaccine and 1.7 million have had their second vaccine.
Officials said the milestone brings people “one step closer to safely seeing our friends and family again”.
Ministers have pledged that all adults will be offered a vaccine by the end of July.
Officials said that 95% of people aged 65 and over have had their first dose.
And nine in 10 of those clinically extremely vulnerable have received a first jab.
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