The British government carved England into three tiers of coronavirus risk on Monday in a bid to slow a resurgent outbreak, putting the northern city of Liverpool into the highest-risk category and shutting its pubs, gyms and betting shops.
Prime Minister Boris Johnson said the three-tier national system was designed to "simplify and standardise" a confusing patchwork of local rules over what residents can and cannot do. Johnson said shops, schools and universities would remain open in all areas.
He told lawmakers in the House of Commons that the goal was to save lives and prevent hospitals becoming overwhelmed without "shuttering our lives and our society" through a new national lockdown.
But pubs, restaurants and other businesses are pushing back, arguing that they are not to blame for rising infections.
After falling during the summer, coronavirus cases are rising in the UK as winter approaches, with northwest and northeast England seeing the steepest increases.
Liverpool has one of the country's most severe outbreaks, with more than 600 cases per 100,000 people, even more than the hard-hit European cities of Madrid and Brussels.
Under the new measures, areas in England are classified at medium, high or very high risk, and placed under restrictions of varying severity.
Areas in the lowest tier will follow existing national restrictions, including a 10pm curfew on pubs and restaurants and a ban on more than six people gathering. In areas at high risk, members of different households are barred from meeting indoors.
The "very high" risk tier will face restrictions including closing pubs and, if local authorities want, other venues such as gyms and casinos.
Liverpool was the only area put into the top category Monday, but Johnson said authorities were still talking with other local leaders across the north of England.
Under the new measures, pubs, gyms, leisure centres, betting shops and casinos in Liverpool will close beginning Wednesday.
Liverpool Mayor Steve Rotheram said his city and others will need financial support and must know exactly what the exit strategy would be from the measures, which are set to be reviewed after a month.
Keir Starmer, leader of the opposition Labour Party, said the measures might not go far enough.
"I am now deeply sceptical that the government has actually got a plan to get control of this virus, to protect jobs or retain public trust," he said.
The UK has experienced Europe's deadliest outbreak, with an official death toll of 42,875.
Health officials say Britain is at a tipping point in the outbreak, with strong action needed to prevent hospitals being overwhelmed at a time of year when they are already at their busiest with flu and other winter illnesses.
Stephen Powis, medical director of the National Health Service in England, said there are currently more people in hospital with the virus than there were when the country went into its national lockdown in March.
He said three temporary Covid-19 hospitals in northern England that were mothballed when the outbreak receded over the summer are being readied to admit patients once again in the coming weeks.
England's deputy chief medical officer, Jonathan Van-Tam, said Monday that while northern England has the highest infection rates, cases are on the rise across the country.
"The epidemic this time has clearly picked up pace in the north of England earlier than it did in the first wave. And that almost certainly relates to the fact the disease levels in the north, and certainly in the northwest, never dropped as far in the summer as they did in the south," Van-Tam told a news conference.
But, he added: "This is a nationwide phenomenon now."
The government has announced a support package to pay two-thirds of the salaries of employees of companies that are told to close, but many in the pub and restaurant sector say that is not enough to save already struggling businesses.
Bar and restaurant owners say the government has not shared any evidence backing up the claim that they are the major transmission sources of the virus.
Manchester City Council leader Richard Leese said data from the city's public health officials "seems to demonstrate that there is not a particular connection between bars and restaurants and the transmission of Covid".
But Calum Semple, professor of outbreak medicine at the University of Liverpool and a member of the government's Scientific Advisory Group for Emergencies, said "most of the outbreaks are happening within and between households, and then after that, it's in the retail and hospitality sector".
"Alcohol and people's behaviour are well known to be factors that result in relaxation of one's adherence to regulations, let's put it politely," Semple told the BBC.
The measures announced Monday apply to England. The rest of the UK is under similar, and sometimes tougher, restrictions. In Scotland's two biggest cities, Glasgow and Edinburgh, pubs have been closed for 16 days to suppress the outbreak.