Boris Johnson was among a record number of more than 600,000 people to receive a Covid-19 vaccine dose in a single day, NHS England has said.
Some 636,219 first and second doses were administered in England on Friday – the highest daily amount since the NHS vaccination programme began.
NHS staff also delivered a record weekly number of vaccines, with more than 2.7 million people receiving the jab over the past seven days.
The Prime Minister was given his first dose of the Oxford/AstraZeneca vaccine on Friday at St Thomas’ Hospital in central London.
It came as NHS chief executive Sir Simon Stevens had his jab at Westminster Abbey on Thursday – the same day the health service hit another major milestone by inoculating more than half of England’s adult population.
Mr Johnson said: “Like the rest of the country I am immensely proud of the progress we have made so far in rolling out vaccinations.
“There is still further to go and I encourage everyone to take up the offer when asked to do so.
“I received my first vaccine yesterday and would like to thank the brilliant NHS staff I met, alongside the teams and volunteers working across the UK to deliver this vital protection.”
More than 22.8 million people have now had at least one dose of the vaccine, while a further 1.5 million second doses have also been administered.
This week’s total of 2,761,890 first jabs was around 200,000 higher than the previous busiest week, NHS England said.
Vaccines are being delivered at more than 1,600 sites across the country, ranging from cathedrals and mosques to stadiums and museums.
Health Secretary Matt Hancock said: “It’s fantastic that we have had a new record day of jabs done in a day.
“This milestone is thanks to a massive team effort.
“The NHS, local government, armed forces and volunteers have worked tirelessly to deliver jabs to the most vulnerable in our country.”
NHS chief executive Sir Simon added: “As a result of this bumper week, we’ve now already vaccinated over half of people in my age group, aged 50-54, and I’d urge everyone who’s now being invited to take up the offer.
“We’ve got really good supply this coming week as well, so if you’re aged 50-plus, now’s a great time to book in for your NHS Covid jab.”
It comes as NHS England told health leaders on Wednesday to expect a significant shortfall in vaccine doses from March 29 for about four weeks.
The slump could mean the under-50s might have to wait until May to get a vaccination, despite doctors having planned to start on that group in April.
Mr Johnson said a delay in deliveries from India and the need to retest a batch of 1.7 million doses was behind the issues with vaccine supply in April.
But he said the drop in available doses would not have an impact on the target to offer all adults a first dose by the end of June.