An 82-year-old man has become the first person in the world to receive the Oxford-AstraZeneca vaccine since it was approved for use in the UK.
Brian Pinker, a kidney disease patient on dialysis at Oxford's Churchill hospital, was the first to receive the jab on Monday morning.
The retired maintenance manager said he was looking forward to spending his 48th wedding anniversary with his wife, Shirley, in February.
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The second person to receive the jab was Trevor Cowlett, an 88-year-old music teacher, while the third was Professor Andrew Pollard, director of the Oxford Vaccine Group and a paediatrician working at the Oxford University Hospitals.
Around 53,000 doses of the Oxford University jab are initially being rolled out at six hospital trusts in Oxford, Sussex, Lancashire, Warwickshire, and two in London.
The bulk of the supplies will then be sent to more than 700 GP-led services and care homes.
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Image:Trevor Cowlett being vaccinated
Image:Trevor Cowlett being vaccinated
The government hopes it will deliver tens of millions of doses within months, with the reported goal of administering two million per week.
It is the second vaccine to be rolled out in the UK, after the Pfizer/BioNTech vaccine was first given to grandmother-of-four Margaret Keenan on 8 December.
Image:Mr Cowlett is an 88-year-old music teacher
Image:Mr Cowlett is an 88-year-old music teacher
Health Secretary Matt Hancock told Sky News it was a "big British success story, starting today".
But he said that fighting the virus was "a massive national effort".
"It isn't about blame, it's about how we collectively, as a society, keep this under control for the next couple of months… until the vaccines can make us safe," he said.
"We obviously have the very positive news this morning of the Oxford-AstraZeneca vaccine started to be rolled out - it's a triumph of British science that we've managed to get to where we are, but this new variant does make it so much harder to control the virus in the meantime."
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He added that from today, there were "700 vaccination sites open across the UK, and by the end of the week it's due to be over 1,000".
Mr Hancock had earlier said: "This is a pivotal moment in our fight against this awful virus and I hope it provides renewed hope to everybody that the end of this pandemic is in sight."
So far, around one million people in the UK have received the other approved vaccine, which is produced by Pfizer and BioNTech.
Image:Professor Andrew Pollard being vaccinated
Image:Professor Andrew Pollard being vaccinated
The Oxford-AstraZeneca vaccine, which was approved on 30 December, is cheaper and easier to store and transport.
In a shift from practices in the US and elsewhere, Britain plans to administer patients second doses of both vaccines within 12 weeks of the first shot rather than within 21 days, to accelerate immunisations across as many people as quickly as possible.
The government's deputy chief medical officer, Professor Jonathan Van-Tam, said on Sunday that decision is "the right thing to do for the nation as a whole."
Professor Stephen Powis, national medical director of NHS England, described the rollout of the Oxford-AstraZeneca vaccine as "another turning point in our way out of this pandemic".
The UK has secured 100 million doses of the Oxford-AstraZeneca vaccine as part of its contract - enough for most of the population.
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The spread of the new more transmissible variant has forced the government to prioritise giving the first dose of the vaccine to as many people as possible, rather than concentrating on giving a smaller group of people the full two doses first.
Following his jab, Mr Pinker said: "I am so pleased to be getting the COVID vaccine today and really proud that it is one that was invented in Oxford.
"The nurses, doctors and staff today have all been brilliant and I can now really look forward to celebrating my 48th wedding anniversary with my wife Shirley later this year."
Image:Brian Pinker was the first person to receive the vaccine
Image:Brian Pinker was the first person to receive the vaccine
Sam Foster, chief nursing officer at Oxford University Hospitals NHS Foundation Trust, who administered the vaccine to Mr Pinker, said: "It was a real privilege to be able to deliver the first Oxford vaccine at the Churchill Hospital here in Oxford, just a few hundred metres from where it was developed.
"We look forward to vaccinating many more patients and health and care staff with the Oxford vaccine in the coming weeks which will make a huge difference to people living in the communities we serve and the staff who care for them in our hospitals."
The UK is currently battling an acute outbreak, recording more than 50,000 new COVID-19 infections each day over the past six days.
On Sunday, it reported another 54,990 cases and 454 virus-related deaths - taking the official number of deaths from the virus to 75,024.
Analysis by Ashish Joshi, health correspondent
It is a landmark moment described as a "game changer" or a "turning point".
The Oxford-AstraZeneca vaccine might prove to be just that.
It's more accessible and affordable. This vaccine can be stored at normal fridge temperatures. That means transport and distribution will not be the logistical challenge posed by the Pfizer/BioNTech vaccine.
Hospitals first and then straight to GP hubs for mass roll out. It can go to care homes too.
The second dose does not be need to administered for up to 12 weeks. That is a much longer window. So the government can concentrate on more people can having just the first dose that still offers high levels of protection.
This is the vaccine backed by government from the start. A home grown effort which means there should be no supply issues. Hopefully there will not be a lag between production and actually getting it into the arms of people.
But while there was a sense of euphoria at the launch of the Pfizer/BioNTech vaccine last month in Coventry, today's landmark moment was a much more subdued affair.
I think that is because we understand we are in the grip of a deadly surge in infections. Hospitals are being overrun with admissions and staff are under more pressure than they were during the first wave.
We know that this vaccination programme is critical in leading us out from the pandemic but we will not see its effect until late spring.
And that is only if mass vaccinations can take place at great speed.
Our scientists have condensed years of work into months. It is an incredible achievement. But all that effort to save lives will mean much less unless it is matched with the same determination and urgency to get as many people immunised as quickly as possible.
