Denmark announced on Friday local time it would close cinemas, theatres and concert halls, and restrict restaurant opening hours over a record number of daily COVID-19 cases, accelerated by the Omicron variant.
The government also plans to close other gathering places such as amusement parks and museums.
"Theatres, cinemas and concert halls, they will have to close," Prime Minister Mette Frederiksen told a news conference.
"We need to limit our activity. We all need to limit our social contacts," she added.
The measures will come into force on Sunday morning for four weeks, the government said.
This is a sharp turnaround for the Nordic country, which had lifted all restrictions on 10 September, before reintroducing a corona pass at the beginning of November and then announcing a first round of restrictions last week.
Dealing with new record numbers on a daily basis, the government has accelerated the rollout of booster doses of COVID-19 vaccines, authorised an anti-COVID pill treatment by US drug manufacturer Merck for serious cases and started vaccinations of children aged five to 11.
The Scandinavian country recorded a new all-time high of more than 11,000 cases in the past 24 hours, Ms Frederiksen said.
Denmark, which sequences more samples than many other countries, is among those countries with the highest numbers of confirmed Omicron cases.
More than 2,500 cases of the reportedly more transmissible variant have been recorded in the last 24 hours.
Restaurants and nightclubs will need to close at 11pm, instead of the current limit of midnight, and alcohol sales will be banned after 10pm.
The government said parliament had approved the measures.
Queen Margrethe II postponed celebrations marking her five decades on the throne originally set for 14 January until "the end of the summer", the palace said.
Unlike during earlier virus waves, Ms Frederiksen said the government still planned to re-open schools after the holidays, even though the Christmas break had already been extended to counter the surge.
"Our aim is still to keep society as open as possible," she said, adding that more restrictive measures introduced in the spring of 2020 could be avoided "because we have vaccines".
Denmark has reported a total of 600,468 cases of COVID-19 since the start of the pandemic and 3,054 associated deaths.
About 500 people are currently hospitalised, including a few dozen in intensive care. Hospitals expect the number of admissions to hit 1,000 in the country of 5.8 million people.
Ireland introduces restrictions
Bars and restaurants will also close from 8pm from Sunday until 30 January in Ireland in a bid to slow the spread of the Omicron variant, Prime Minister Micheal Martin announced on Friday.
Mr Martin told the nation that "all across Europe there needs to be very strong and immediate reduction in contacts between people" as he announced the measures, which he acknowledged would be "deeply disappointing for many".
Mr Martin also announced that indoor and outdoor events held earlier than 8pm would be limited to 50 per cent capacity, while weddings will be allowed a maximum of 100 guests.
Irish Prime Minister Micheal Martin speaking to the media in Dublin. Source: Press Association
The measures were taken following advice from health officials on the new strain.
"It spreads so aggressively throughout all age groups that we are likely to see infections at a rate that is far in excess of anything we've seen to date," warned Mr Martin.
"None of this is easy. We are all exhausted with COVID and the restrictions it requires.
"The disappointments and the frustrations take a heavy toll on everyone. But it is the reality that we are dealing with. We cannot wish it away. And there is no silver bullet to fix it," he added.
Britain records record numbers for third day
The British government, in the meantime, reported 93,045 new COVID-19 cases on Friday, a third consecutive record daily tally, as the Omicron variant fuels a surge in infections across the country.
The latest data brings the total number of infections during the pandemic to more than 11.1 million, while the UK also registered a further 111 deaths from the virus, taking the death toll to more than 147,000.
Scotland First Minister Nicola Sturgeon said Omicron is now the country's dominant COVID-19 strain, adding "the tsunami I warned about a week ago is now starting to hit us".
And Welsh leader Mark Drakeford told citizens to brace for the "storm of Omicron" having announced the country's nightclubs will close after 26 December and social distancing reintroduced in shops and workplaces.
An overnight walk-in vaccine clinic in London, where a mass booster drive is being rolled out. Source: Press Association
Britain is currently rolling out a mass booster drive in order to vaccinate as many people as possible before the end of the year.
Prime Minister Boris Johnson said the aim was on "trying to make sure that we not only have the fastest vaccine rollout in Europe" but also "to avert some of the more damaging consequences of Omicron".
Booster shots in France
France will from next month reduce the time between second and third COVID-19 vaccination injections to four months and require people to show proof of vaccination to enter some venues, Prime Minister Jean Castex said on Friday.
The gap between shots is currently five months but the French government is concerned about the spread of the Omicron COVID-19 variant.
Mr Castex said that big public parties and fireworks would be banned on New Year's Eve and recommended that people - even if vaccinated - test themselves before attending year-end parties.
To increase pressure on people to get vaccinated, the government will present a bill early next year to change the French health pass into a vaccination pass. That means people will have to be vaccinated to enter restaurants or use long-distance public transport.
Under current rules, a recent negative test can serve as a health pass even without vaccination.
France is increasing pressure on its citizens to get vaccinated. Source: EPA
"We cannot allow that the refusal of a few French people to get vaccinated affect the life of the entire country," Mr Castex said in a televised speech.
He said the rapid spread of the Omicron variant was also behind restrictions being imposed on travel from Britain to France from Saturday.
Mr Castex said that while the fifth wave of COVID-19 in France - driven by the Delta variant - was close to its peak, the country had already registered several hundred cases of the Omicron variant and that health authorities expected it to spread quickly and become dominant early next year.
In the past three days, the seven-day moving average of new cases in France has been more than 50,000 per day.
Germans told to brace for 'massive fifth wave'
Germany on Friday designated France and Denmark as high risk zones for the transmission of coronavirus and will impose quarantine on unvaccinated travellers from the two countries, a public health agency said.
The requirement will be imposed from Sunday and will also apply to travellers from Norway, Lebanon and Andorra, with those unvaccinated or who have not recovered from the virus subject to quarantine with the possibility of testing on day five.
Health Minister Karl Lauterbach said earlier on Friday that Germany, battered by a recent rise in COVID-19 cases, must brace for a "massive fifth wave" due to the new Omicron variant.
A worker outside a mass vaccination centre in Berlin. Source: EPA
"We must prepare for a challenge that we have not yet had in this form," Mr Lauterbach told reporters, adding that even if the variant was "milder" it may make "no difference".
Were the virus to be less serious than other variants, this might "keep deaths low for two to three weeks, before the growth of the virus would eat up this advantage", the minister said, underlining that a difficult period ahead was "inevitable".
Germany has reimposed health restrictions following high case numbers, barring unvaccinated people from restaurants and non-essential commerce.
Case numbers have declined slightly but the spread of the more infectious Omicron variant, first identified in South Africa, threatens to send new infections up again.
