This comes as all over-50s are now allowed to book their appointments for the Covid vaccine.
Speaking at a Downing Street press conference today Health Secretary Matt Hancock doubled down on the pledge to vaccinate all over 50s by April 15.
When questioned at the press conference Mr Hancock said supply was always “lumpy” but there would be enough vaccines to meet demand.
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NHS letter in full
The letter from NHS England has said there will be a “significant reduction” in weekly vaccine supply from the end of March.
Addressed to local health leaders it states “volumes for first doses will be significantly constrained”.
The letter from NHS England leaders reads: “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.”
It adds: “We must take this time to deliver protection to the most vulnerable.”
“They now currently predict this will continue for a four-week period, as a result of reductions in national inbound vaccines supply.”
NHS chief commercial officer Emily Lawson, who wrote the letter, added: “Our vaccination delivery programme was designed to be flexible, scaled up and diversified in line with fluctuating international vaccine supplies.
“Thank you for your continued efforts, and, as ever, we are hugely grateful for everything that you are doing to make the NHS’s part in the delivery of this programme the success that it is.”
However, Health Secretary Matt Hancock argued the NHS letter warning vaccine supply will face a “significant reduction” was a “standard” technical letter.
He told the Downing Street press conference: “Vaccine supply is always lumpy and we regularly send out technical letters to the NHS to explain the ups and downs of the supply of the future weeks and what you are referring to is a standard one of those letters.”
“While we deliver on that commitment, we also want to ensure that this offer reaches everyone in groups one to nine.
“At the same time as opening up offers of vaccinations to all those who are 50 or above, we are going to do whatever it takes to reach all those in the most vulnerable groups who haven’t come forward yet before we move onto the next cohort, which is people in their 40s.
“Before we forge ahead I want us to be confident that we’ve done everything we can to protect those most in need of protection and we will do all we can and do everything necessary to deliver the supplies that are contractually committed to protecting people in this country.”
He said today: “The Oxford/AstraZeneca vaccine was produced from research funded by the UK Government, tens of millions of pounds. We set up the supply chain, not just here in the UK but we helped set up the supply chain in the EU.
“This vaccine is provided at cost to the whole world … and we legally signed a contract for delivery of the first 100 million doses for people here, for people in the UK.”
He said Ms von der Leyen had said before “there should not be restrictions on the export of vaccines by companies where they are fulfilling contractual responsibilities”.
“So, the supply of vaccines from EU production facilities to the UK is indeed fulfilling contractual responsibilities and we fully expect those contracts to be delivered on,” he added.