Foreign Secretary Dominic Raab has defended the “balanced, targeted and proportionate” new coronavirus measures amid criticism from some scientists.
In England, people are being told to work from home if they can and rules on face coverings have been expanded.
The measures have exposed a split among scientists. Prof John Edmunds, who advises the government, said they did not go “anywhere near far enough”.
But other scientists say they hope they are a shift towards a coherent policy.
On Tuesday, tighter restrictions were announced in all four UK nations.
Other measures introduced in England include a 10pm closing time for pubs and restaurants and the number of people allowed at weddings has been halved. The fines for breaking the rules are set to increase to £200 on the first offence.
Hospitality venues will also have to close early in Scotland and Wales - but Scotland has gone further, banning people from visiting other people’s homes from Wednesday. Northern Ireland has also already banned households mixing indoors.
In a television broadcast on Tuesday night, Prime Minister Boris Johnson said “we must reserve the right to go further” if cases continue to rise.
He said he was “spiritually reluctant” to infringe on people’s freedoms, “but unless we take action, the risk is that we will have to go for tougher measures later, when the deaths have already mounted”.
In an interview on the Today programme, Prof Edmunds said the lockdown in March which closed schools, the hospitality sector and businesses, had involved a combination of many different measures which brought the R number - which measures how quickly the virus is spreading - down from 2.7 to 0.7.
To stop the epidemic from growing any further, a large range of measures was needed, he said, and cast doubt on the R number being below 1 by Christmas. “I suspect not. There’s a chance, of course there’s a chance,” he said.
“To slow the epidemic down will mean putting the brakes on very hard. I suspect we will see very stringent measures coming in through the UK but it will be too late,” he warned.
Another scientist, Prof Carl Heneghan, from Oxford University, wrote to the government on Monday saying there should be targeted measures to protect the vulnerable because suppression of the virus was increasingly unfeasible.
Speaking to the BBC’s Today, he said the measures seemed to show the emphasis of public policy was moving towards personal responsibility, similar to Sweden.
“There’s a clearer aim that’s happening,” he said. “We’re starting to understand that we’re trying to control the spread of infection as opposed to suppress it.”
He added it was important to give these new measures time to work, maintain a clear and consistent public message and not to panic.
The government’s chief medical adviser, Prof Chris Whitty, is understood to believe it is inevitable England will to have to follow Scotland’s latest move, according to the Times.
Mr Raab defended the government’s strategy, saying there would always be the “Goldilocks criticism - too much or too little”.
He struck a more optimistic tone, saying if people followed all the measures - and no one thinks they are immune - “we will get through this and we will get to Christmas not in a national lockdown”.
“Overwhelmingly the public have responded every time but increasingly there’s been a small minority where compliance has frayed,” he added.
“We know that in bars and restaurants, particularly after people have had a few drinks, as you go into the later hours of the evening, that there’s a risk that the compliance with the guidance ebbs a little bit,” he added, defending the move to close pubs at 10pm.
He added that the effectiveness of the measures would be monitored but there was no fixed time to them. In his address, the prime minister warned they could last up to six months.
Mr Johnson will face further scrutiny from MPs in the House of Commons later during Prime Minister’s Questions.
The devolved nations have their own powers over coronavirus restrictions.
Scotland’s Deputy First Minister John Swinney acknowledged the new rules banning people from visiting other people’s homes were “difficult and disruptive” and said they would be reviewed every three weeks.
“No one wants to have this in place a moment longer. The more public compliance, the more successful we will be,” he told BBC’s Breakfast.
Wales’ First Minister Mark Drakeford urged people not to let the virus “take a hold of our lives again”, and Northern Ireland’s First Minister Arlene Foster said tougher restrictions should act as a “wake-up call” that “we are not out of the woods”.
And the number of UK cases rose by 4,926 on Tuesday, government figures showed, with deaths increasing by 37.
What are the new rules?
- Office workers are being told to work from home again if possible
- Penalties for not wearing a mask or gathering in groups of more than six will increase to £200 on the first offence
- From Thursday 24 September, all pubs, bars and restaurants will be restricted to table service only. Takeaways can continue
- Also from Thursday, hospitality venues must close at 22:00 - which means shutting then, not calling for last orders (in Scotland the same curfew rule comes into force on Friday)
- Face coverings must be worn by all taxi passengers from Wednesday
- Retail staff and customers in indoor hospitality venues will also have to wear masks from Thursday, except when seated at a table to eat or drink
- From Monday 28 September, only 15 people will be able to attend weddings and civil partnerships, in groups of six. Funerals can still take place with up to 30 people
- Also from 28 September, you can only play adult indoor sports in groups of less than six
- The planned return of spectators to sports venues will now not go ahead from 1 October
- People across Scotland are being advised not to visit other households indoors from Wednesday 23 September onwards. This will become law from Friday
- There will be exceptions for those living alone, or alone with children, who form extended households. The rules will also not apply to couples who do not live together, or to tradespeople or for the provision of informal childcare - such as by grandparents
- From Friday, pubs and restaurants will have to close by 22:00
- The first minister urged people not to book overseas travel for the October school holiday
- Pubs, cafes and restaurants in Wales will have to close by 22:00 from Thursday - and sales of alcohol from off-licences and supermarkets will also be stopped after that time
- Pubs will also be required to provide table service only
In Northern Ireland:
- From now, people cannot meet anyone who they don’t live with inside their home
- There are only limited exceptions.
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