Angela Merkel has implored Germans to further reduce their social contacts before Christmas or risk losing loved ones, in an unusually emotional speech to parliament.
The German chancellor was furious in tone, her voice breaking, as she told MPs the death rate was "unacceptable" and urged tighter measures.
"If we have contact with too many people before Christmas and subsequently it turns out to have been the last celebration with the grandparents, then we will certainly have been neglectful, and we just should not do that," she said.
She urged those who would be visiting elderly or vulnerable loved ones to follow scientific advice, and reduce contacts to an absolute minimum for a week before meeting.
Merkel said the pandemic's progress in Germany was extremely worrying, with numbers rising despite tighter lockdown regulations introduced five weeks ago.
She said she was therefore in favour of following the guidelines of scientists from the National Academy, Leopoldina, to tighten rules ahead of Christmas and introduce a harder lockdown immediately afterwards.
"There are 14 days to go until Christmas," Merkel said. "And I tell you what worries me, is how it is developing right now. There are 3,500 more cases than there were a week ago and we need to do everything we can to ensure that we don't get the exponential growth we have had."
On Wednesday, Germany reported a record 590 deaths, more than 100 more than a week ago, when the previous record since the pandemic began was reached. Almost 21,000 new cases were registered and 4,257 ICU beds were occupied with Covid-19 patients. Merkel compared these figures with those from 29 September to illustrate the speed of the escalation. Then there were 1,827 new cases, 352 ICU beds were occupied and there were 12 deaths, she said.
In September, Merkel was accused of alarmism after suggesting that by Christmas Germany could be recording 19,200 cases a day, a figure which has long since been surpassed.
Merkel was addressing a debate about the government's 2021 budget, which will require a debt brake rule anchored in the constitution to be overruled for only the second time, in order to cover the extra costs of about ?180bn required to tackle the pandemic.
In the first few months of the health crisis, Germany was viewed as a role model internationally over its virus management, including an efficient track-and-trace system, speedy lockdowns and extensive testing from early on in the pandemic.
Its overall death rate is, at just under 20,000, still considerably lower than other countries. But it has been rising fast for weeks, with politicians frequently comparing the number of deaths to the daily downing of a passenger plane.
Epidemiologists have said a "prevention paradox", whereby the country's ability to manage the spread of the illness dampened the fear surrounding it to the extent that the narrative quickly took hold that it was less dangerous and contagious than health experts claimed, has helped its subsequent spread.
As she addressed the Bundestag, Merkel was constantly heckled by members of the opposition far-right Alternative für Deutschland (AfD), which has accused the government of exaggerating the seriousness of the virus and killing the economy with its lockdown measures.
Merkel said it was time everyone recognised the virus for what it was, by following the science and reclaiming the facts from anti-vaxxers and those who deny the existence of the virus or downplay it.
She told MPs that after growing up in the communist dictatorship of East Germany, where facts were controlled by the government, she had deliberately chosen to study physics "because I was very sure that while there are many things one can overrule, gravity is not one of them, neither is the speed of light nor other facts, and that will continue to be the case."
She faced a sharp attack from the AfD's joint leader, Alice Weidel, who accused her of "haphazard and grotesque handling" of the pandemic.
Weidel said: "You are locking citizens up and destroying whole branches of industry." She said Merkel's "sledgehammer approach" was to introduce yet another lockdown "which will bring more calamity than benefit".
Christian Lindner, the leader of the pro-business FDP, called on the government to introduced "more predictability" into its coronavirus strategy. "The lifespan of the announcements, the explanations and the code of conduct is getting ever shorter," he said, adding that the strain on the "most important resource to tackle the crisis - the state's ability to act - is getting ever more scarce".
Merkel praised the "creative, inquisitive spirit" of "the best scientists in the world" who have created vaccines, which she called "the light at the end of the tunnel".
Germany is still waiting on vaccine approval by the European Medicines Agency (EMA).
The health minister, Jens Spahn, has said he expects a vaccination programme to start in January and for 5 million people to have been vaccinated by the end of March. One hundred vaccine centres have been set up across the country and a provisional six-stage vaccine programme is expected to last until December 2021.