Covid: All adults able to book coronavirus vaccination in England
People aged 18 and over in England are being invited to book their first Covid-19 jab in what the NHS has described as a "watershed moment".
About 1.5 million texts are due to be sent to people aged 18 to 20 on Friday.
PM Boris Johnson said the speed of the programme was "one of our country's greatest collective achievements".
It comes as a study suggests the epidemic is growing across the nation, with much of the rise being driven by young people.
On Thursday a further 11,007 cases of Covid-19 were reported, the highest daily rise since 19 February, while a further 19 deaths were also recorded.
The government has set a new target to have offered a first dose to all adults by 19 July and a second dose to two-thirds of the over-40s.
The prime minister said: "Offering all adults a jab less than 200 days after the programme launched is one of our country's greatest collective achievements, saving over 14,000 lives so far."
He added reaching the next stage of the programme would see "vaccines accelerate in their race with the virus" and called on people to "finish the job" by coming forward for their jab.
NHS England chief executive Sir Simon Stevens said the health service was "delivering the final push to protect the country".
"This is truly a watershed moment. Whoever you are, wherever you live, if you are aged 18 or older and you are yet to book your Covid jab, today should be the day you make that happen," he said.
"Only months after delivering the world-first first jab, hardworking NHS staff have given more than 60 million vaccinations in England alone, saving thousands of lives and giving the entire country hope for a brighter future."
As of Wednesday more than four in five adults have received a first dose of the vaccine, while 58.2% - or 30.68 million people - are now fully vaccinated.
The BBC has been told that a decision to vaccinate all 12 to 17-year-old children is unlikely to be recommended by UK vaccine experts imminently.
The Joint Committee on Vaccination and Immunisation (JCVI) is expected to make a statement on the matter in the coming days.
Speaking at the NHS Confed Conference on Thursday, England's chief medical officer Prof Chris Whitty said there was currently a "further surge" of coronavirus, with the height of it "still uncertain".
He said he expected a "further winter surge" and said he thought new variants may well lead to booster jabs or revaccination being required over the next two to three years.
Case rates have risen in all regions of England, according to Public Health England's latest survey report, with the North West seeing the highest rate with 196.9 cases per 100,000 people for the week to 13 June.
That compares with 152 per 100,000 people the week before.
Rates are highest among young people with 195.9 cases per 100,000 in those aged 20-29, up from 123.6.
The second highest rates are among 10 to 19-year-olds, at 143.3 per 100,000 up from 100.3.
How to book your jab
In England people can book their vaccination appointment online or by calling 119.
Elsewhere in the UK, people aged 30 and over can get their vaccine in Scotland, although in some parts of Glasgow people aged 18 and over can get a first jab.
In Wales, people aged 18 and over can get the vaccine, with the Welsh government announcing that all adults had been offered a vaccine earlier this week.
In Northern Ireland, people aged 18 and over can book online or call 0300 200 7813.
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