Britain reported 96 more coronavirus deaths on Saturday, taking the number of people who have died within 28 days of a positive test result to 126,122, daily government figures showed.
A further 5,587 people have tested positive for the disease, up 1 per cent from last Saturday's figure of 5,534.
Last Saturday, 121 deaths were recorded, meaning fatalities have fallen by 21 per cent in seven days.
Today's figures marked only the fourth time since the second wave that deaths have dipped to double figures. The last Saturday to see double figures was on October 10.
The figures come as Britain today passed a huge milestone in its fight against coronavirus as the number of adults to have been given a vaccine passed the halfway point - a day after the country recorded a record number of daily jabs.
Health Secretary Matt Hancock hailed the 'national success story' and reiterated that it was 'our way out of this pandemic'.
Government data up to March 18 shows 49.9 per cent of adults had a first dose of the vaccine, with an estimated 73,000 more jabs needed to pass the halfway mark. Those figures are expected to be updated later today.
Yesterday the vaccine drive hit a record high after 660,276 doses were dished out across the country in the previous 24 hours.
Elsewhere in the crisis:A top British scientist who is leading Covid-19 vaccine research warned the Government faces a 'challenge' to deliver all second jabs within 12 weeks due to supply issues;Ursula von der Leyen threatened to halt exports of AstraZeneca vaccines if the EU does not receive its deliveries first, in a worsening row over delayed shipments that has caused international tensions;A government scientist warned foreign trips are 'extremely unlikely' for Britons this summer as Europe struggles to control a surge in coronavirus cases;Politicians across the House of Commons have called for Priti Patel to change coronavirus legislation to allow protests despite lockdown; Billionaire tax exiles, an oil-rich nation and Saudi royals have claimed millions of pounds under the furlough scheme, an investigation reveals; Boris Johnson yesterday joined the millions of vaccinated Britons after receiving his first dose of the Oxford-AstraZeneca jab; Angela Merkel said she will have the Oxford-AstraZeneca vaccine after lifting her government's ban in a stunning U-turn;
Today's new cases figure brings the total number of coronavirus infections since the stat of the pandemic to 4,291,271.
Separate figures published by the UK's statistics agencies for deaths where Covid-19 has been mentioned on the death certificate, together with additional data on deaths that have occurred in recent days, show there have now been 148,000 deaths involving Covid-19 in the UK.
Mr Hancock said today: 'I'm absolutely delighted to tell you that we have now vaccinated half of all adults in the united kingdom.
'It's a huge success and I want to say many, many thanks to all those involved, including the half of all adults who have come forward.'
He added: 'The UK vaccination programme is a big success story. It's down to the hard work of many, many people.'
The vaccine programme had been steadily gaining pace this week, after 529,119 total doses were given out on Tuesday and 581,855 on Wednesday.
Some 26.2million Britons have now received their first dose, the equivalent of half the adult population in Britain, and two million have received both injections.
Despite the promising week, the NHS is gearing up for a significant shortage of vaccine doses next month due to supply issues in India.
The figures come as Britain today passed a huge milestone in its fight against coronavirus as the number of adults to have been given a vaccine passed the halfway point - a day after the country recorded a record number of daily jabs. Health Secretary Matt Hancock (pictured) hailed the 'national success story' and reiterated that it was 'our way out of this pandemic'
A shipment of five million Oxford shots has been delayed, for reasons have not been made clear, with No10 holding talks with New Delhi to get the roll-out back on track.
It means Britons over 40 who were expecting to be called for their appointments next month will need to wait until at least May. Ministers are instead prioritising current stock for over-50s and for people due their second doses.
Dr Jeremy Farrar, Director of Wellcome, welcomed the vaccine milestone.
He said: 'To have vaccinated half of the UK's adult population in under 3 months is remarkable. Soon we'll have covered 99 per cent of those at high risk of dying from Covid-19. The UK should be proud of this achievement and the scientists, healthcare workers and volunteers who got us here.
'But we need to start thinking beyond our borders. The UK has access to 100 million surplus vaccine doses. Almost enough to vaccinate every citizen twice. These doses won't be of use in the UK. It's time we begin sharing doses with those most in need globally.
'This is more than a question of ethics – it is a scientific and economic imperative. If left to spread unchecked in large parts of the world, the virus risks mutating to an extent where our vaccines and treatments no longer work – leaving us all exposed. Science has given us the exit strategy, but it will only work if its benefits can reach the maximum number of people around the world.
NHS England figures show 79 per cent of over-55s in the country had at least one dose of the vaccine by March 14, but London is significantly lagging behind in uptake
Statistics from the MHRA show that while 78 per cent of all first doses were Pfizer jabs between December 8 and January 24, this split reversed between February 7 and March 7 so that it only accounted for 34 per cent. Just nine per cent of all first doses in the week to March 7 (200,000) were supplied by Pfizer
'It is not enough to champion the importance of equitable access – we urgently need confirmed timetables for sharing doses through Covax. The UK should lead the way on this.'
Conservative MPs were also quick to congratulate Health Secretary Mr Hancock after the monumental vaccination figure was reached.
Baroness Morgan tweeted: 'A remarkable achievement - thank you to everyone involved in making this happen. For the first & last time ever I'm sorry not to be over 50!'
Conservative Alicia Kearns, MP for Rutland and Melton, said: 'Half of all adults vaccinated - what a Herculean achievement!'
Tory Rob Butler posted: ''Vaccinating half of all adults in the UK is an astonishing achievement.' The MP for Aylesbury added: 'Thank you to everyone in & around Aylesbury for your contribution.'
MP for Bury St Edmunds Jo Churchill said: 'An incredible milestone - we have now vaccinated half of all adults in the UK. When you receive your invitation please #getthejab!'
And Conservative MP for BurySouth Christian Wakeford put: 'Might be waiting a bit for mine but this is a massive achievement. To everyone who has helped get us this far - Thank you.'
But in an unexpected blow for sun-starved Brits earlier today, Dr Mike Tildesley said there was a danger travellers could bring back new Covid variants which are less susceptible to vaccines.
The Warwick University professor, who is a member of the Spi-M modelling group, warned it means overseas jaunts for the average holidaymaker are in doubt.
Dr Tildesley told the Today programme: 'I think that international travel this summer is, for the average holidaymaker, sadly I think, extremely unlikely.
'I think we are running a real risk if we do start to have lots of people going overseas in July and August because of the potential for bringing more of these new variants back into the country.
'What is really dangerous is if we jeopardise our vaccination campaign by having these variants where the vaccines don't work as effectively spreading more rapidly.'
The good vaccine news came as EU chief Ms von der Leyen threatened to halt exports of AstraZeneca jabs if the EU does not receive its deliveries first, as the row over delayed shipments that has caused international tensions deepened.
The EU chief told the pharmaceutical company it has to come through on deliveries to the bloc or it would block exports of jabs made on its turf.
In an interview with Germany's Funke media group she said: 'We have the option of banning a planned export.
'That's the message to AstraZeneca: you fulfil your contract with Europe first before you start delivering to other countries.'
Her warning came as the European Union struggled to speed up its Covid inoculation campaign, just as many member states are battling rising infection rates that have forced renewed restrictions.
France and Poland have both imposed partial lockdowns as cases begin to soar again in the countries.
Von der Leyen said AstraZeneca had delivered only 30 percent of the 90 million vaccine doses it had promised for the first quarter of the year.
The company has blamed production delays at its EU plants in Belgium and the Netherlands, but European officials are furious that AstraZeneca has been able to deliver its UK contract in full while falling short on the continent.
Britain does not rely on exports of AstraZeneca from the EU – with the vast majority of the UK's 100million jab order from the company being made at home with 10million made in India – but the bloc did block an export of 250,000 jabs to Australia at the start of the month.
Some 26.2million Britons have now received their first dose, the equivalent of half the adult population in Britain, and 2m have received both injections