Britain on Tuesday became the first European country to pass 100,000 Covid deaths, in a grim milestone nearly one year since its first case of the disease.
Another 1,631 deaths were reported on Tuesday, bringing the total to 100,162 from nearly 3.7 million positive cases and overshadowing progress in an unprecedented vaccination campaign.
An ashen-faced Prime Minister Boris Johnson told a news conference just minutes after the official statistics were published that it was "hard to compute" the loss felt by families across the UK.
"I am deeply sorry for every life that has been lost and of course as prime minister I take full responsibility for everything that the government has done," he added.
But he said the government, which has been criticised for its initial response to the outbreak, "did everything that we could to minimise suffering and minimise loss of life".
Opposition Labour leader Keir Starmer called the statistic a "national tragedy".
Britain reported its first cases of the disease almost a year ago, on 29 January, 2020 but Mr Johnson was initially relaxed about the outbreak, despite widespread calls for a lockdown.
As cases rose, he eventually relented, and a lockdown was introduced in March.
Questions have, however, remained about the government's approach, particularly its testing and tracing regime.
At the time of the first lockdown, National Health Service (NHS) England medical director Steven Powis said: "If we can keep deaths below 20,000 we will have done very well".
The stay-at-home order was imposed largely on the back of an Imperial College London study that warned 500,000 could die without severe measures, and 250,000 with less stringent regulations.
Since then, the country has endured another two waves of the virus, and is currently mired in its third and deadliest bout, blamed on a new variant that hit before Christmas.
NHS England chief Simon Stevens said some 250,000 people had so far required hospital treatment after catching the virus.
"This is not a year that anyone is going to want to remember nor is it a year that anyone across the health service will ever forget," he added.
'Tough period' ahead
Mr Johnson promised that "we will come together as a nation to remember everyone we lost and to honour the selfless heroism of all those on the frontline who gave their lives to save others" once the pandemic was over.
Although case numbers have fallen over the past week, Chris Whitty, the government's chief medical officer, warned that the death toll would remain high for a while.
"I think we have to be realistic that the rate of mortality... will come down relatively slowly over the next two weeks," he said.
Health Secretary Matt Hancock said that the situation could become even worse if people did not stick to the rules.
"I know how hard the last year has been, but I also know how strong the British public's determination is and how much we have all pulled together to get through this," he said.
"We cannot let up now and we sadly still face a tough period ahead. The virus is still spreading and we're seeing over 3,500 people per day being admitted into hospital," he added.
Britain is banking on its vaccination drive to beat the virus, and has now administered jabs to 6,853,327 people, according to the latest figures.
Mr Johnson on Tuesday also urged the European Union not to impose export controls on vaccines amid discontent over a delay in rolling out pharmaceutical group AstraZeneca's jab to member countries.
"I don't want to see restrictions on the supply of PPE (personal protective equipment) across borders, drugs across borders, vaccines or their ingredients across borders," he said.
Further travel restrictions have been introduced.
In December, the UK became the first country in the world to approve the Pfizer-BioNTech COVID-19 vaccine and has set itself the task of offering jabs to everyone 70 and older, those who are clinically vulnerable, frontline health and social care workers and older adults in care homes by mid-February.
A total of 6,853,327 people have now received a first dose and 472,446 a second dose.
