All but essential retail outlets will be forced to close from Friday – tougher measures than in either Scotland or tier 3 areas of England – in what Cardiff is calling a “fire break”.
Mark Drakeford, the Welsh first minister, said the only alternative to the drastic crackdown – starting at 6pm on 23 October – would be an “open-ended” lockdown, as in March.
It was a “short, sharp shock to turn back the clock, slow down the virus and give us more time”, he said.
“If we do not act now, it will continue to accelerate and there is a very real risk that our NHS will be overwhelmed,” Mr Drakeford warned.
The lockdown will pile fresh pressure on Boris Johnson to take tougher action, after the prime minister refused the two-week “circuit break” recommended by his scientific advisers.
All gatherings with people in a different household throughout Wales will be banned – both indoors and outdoors – with the exception of small Remembrance Sunday commemorations.
Although schools will remain open in Wales, only year 7 and 8 pupils will return to secondary schools after the half-term holiday, on 2 November.
As in the first lockdown, everyone will be “required to stay at home”. “The only exceptions will be critical workers and jobs where working from is not possible,” the First Minister said.
Mr Drakeford insisted the lockdown will end on 9 November, even though the benefits it would bring would not show up in the figures by that date.
“That is not the test to set. We know now that we will not see the benefit within the two weeks of the fire breaker period,” he told a press conference.
The lockdown comes after Wales imposed a travel ban on anyone travelling from hotspot areas in England, accusing the prime minister of failing to act.
Most of Wales has been under harsh restrictions for several weeks – including a bar on travelling in or out of county areas without reasonable excuse – but they have failed to bring down infections.
Almost 1,000 new Covid-19 cases were recorded again on Sunday, taking the nation's seven-day infection rate to over 130 per 100,000 people.
Cardiff's infection rate is much higher and has risen significantly, to 270 cases for every 100,000 residents.
Mr Drakeford said the number of people in hospital was “growing every day”, with “critical care units already full”. Without action “even more people will die from this deadly virus”, he warned.
The prime minister’s spokesman rejected a similar crackdown in England, saying he “continues to believe that targeted local action in areas of high prevalence of the virus is the correct course”.
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