British Prime Minister Boris Johnson on Monday ordered pubs in Liverpool to shut as part of a new strategy to tackle a surge in coronavirus cases, as staff at three field hospitals across the country were told to prepare for a wave of admissions.

The northwest English city is the first to be placed at "very high risk" under a new three-tiered system designed to bring order to what has become a complex web of local restrictions.

Johnson addressed the nation to explain the decision, saying the latest figures "are flashing at us like dashboard warnings in a passenger jet and we must act now".

Pubs shut in Liverpool
Police patrolled on horseback in Liverpool Saturday as people stayed out late partying. Photo: AFP / Lindsey Parnaby

He earlier told MPs that he could not allow Covid-19 to "let rip" and risk the death toll -- the highest in Europe at almost 43,000 -- spiralling even higher.

"This is not how we want to live our lives," the Conservative leader, who himself was hospitalised with coronavirus in April, told the House of Commons.

"But this is the narrow path we have to tread between the social and economic trauma of a full lockdown and the massive human and economic cost of an uncontained epidemic."

British Prime Minister Boris Johnson
Prime Minister Boris Johnson has been heavily criticised for his government's response to the outbreak. Photo: AFP / Daniel LEAL-OLIVAS

Inter-household mixing will be banned indoors and in private gardens while pubs, bars, gyms, betting shops and casinos will close from Wednesday in Liverpool, which has a population of about 1.5 million.

People will be advised not to travel in and out of these areas.

Johnson said businesses forced to close would be supported under a new government programme to fund two-thirds of an employee's monthly wages, as well as extra support for local contact tracing and enforcement.

Pubs shut in Liverpool
Almost 14,000 new coronavirus cases were reported across the UK on Monday. Photo: AFP / Paul ELLIS

Other areas of England will be classed either as "medium", in which current nationwide rules limiting social gatherings to six will apply, or "high", where different households are banned from mixing indoors.

Whole swathes of northern England already facing local restrictions will automatically enter the "high" risk tier.

Earlier, the state-run National Health Service (NHS) announced that three field hospitals across northern England, in Manchester, Sunderland and Harrogate, would be mobilised to accept new patients.

They are among a string of temporary hospitals, named after nursing pioneer Florence Nightingale, put up by the military in conference centres and stadia coronavirus as swept across the UK earlier this year.

Pubs shut in Liverpool
A street sign advises members of the public to "Maintain Social Distance" in Liverpool. Photo: AFP / Paul ELLIS

Testing for hospital staff is also being stepped up in high-risk areas, as health officials warned infection rates were rising across the country and in all age ranges, not just the young.

Almost 14,000 new coronavirus cases were reported across the UK on Monday, with 50 further deaths.

"The number of cases has quadrupled in the last three weeks. There are now more people in hospital with Covid than when we went into lockdown on March 23," said Johnson, who has faced criticism for his handling of the outbreak.

A UK-wide stay-at-home order was lifted in June but England, whose health policy is controlled by the UK government, and the devolved administrations in Wales, Scotland and Northern Ireland have all since imposed new measures to stop the spread of the virus.

They include blanket restrictions on social gatherings, in addition to more localised measures.

Pubs in England must shut at 10:00 pm, while pubs and other licensed premises in central Scotland shut entirely last Friday for 16 days.

Johnson is determined to avoid closing schools and universities again.

But the focus on shutting hospitality venues has sparked anger.

The Night Time Industries Association, an industry body, said Monday it was mounting a legal challenge against the restrictions, calling them "hugely disproportionate and unjust".

Main opposition Labour leader Keir Starmer meanwhile accused Johnson of "running to catch up with the virus that he has lost control over long ago".

Separately, the culture ministry announced ?257 million ($336 million, 284 million euros) to help more than 1,300 arts organisations across England.

The money "will allow our wonderful theatres, museums, music venues and cultural organisations to survive this crisis and start putting on performances again", culture secretary Oliver Dowden said.

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