The further easing of coronavirus restrictions in England – due to come in this weekend – has been postponed for at least two weeks, amid concerns over an increase in coronavirus cases.
Casinos and bowling alleys will remain shut, with Boris Johnson saying it was time to “squeeze the brake pedal”.
Wedding receptions of up to 30 people were meant to be allowed as part of the changes but cannot yet happen.
Face coverings will be mandatory in more indoor settings, such as cinemas.
And people attending places of worship will also be among those required to wear face coverings, in a change that will be applied from next weekend.
The rethink follows new restrictions for people in parts of northern England, after a spike in virus cases.
At a news conference in Downing Street, the prime minister said progress against coronavirus continues, with the daily and weekly number of deaths falling, but warned that some European countries are “struggling” to control it. The UK must be ready to “react”, he said.
Highlighting the latest figures from the Office for National Statistics, he added: “The prevalence of the virus in the community, in England, is likely to be rising for the first time since May.”
Mr Johnson said planned reopenings for 1 August would be delayed for at least a fortnight.
That means venues such as casinos, bowling alleys, skating rinks and remaining close contact services must remain closed until 15 August.
Indoor performances will also not resume, pilots of larger gatherings in sports venues and conference centres will not take place, and the planned expansion of wedding receptions to allow up to 30 people will not be permitted.
Spectators were due to watch the first two days of two county cricket matches, while fans were at the World Snooker Championship when it started on Friday. The tournament will now go ahead without spectators until at least 15 August, which is when the final is schedule to begin.
Separately, face coverings will be compulsory in more indoor settings where people are likely to come into contact with people they do not know, such as museums and places of worship, from next weekend. They are already required in shops, banks, airports and other indoor transport hubs.
The prime minister said the rules for face coverings would become enforceable in law from 8 August.
Also at Friday’s news conference, England’s chief medical adviser warned that it might not be possible to further ease lockdown.
Asked whether it was safe for England’s schools to open fully to all pupils at at times in the autumn, Prof Chris Whitty said it was a “difficult balancing act” but “we have probably reached or neared the limits of what we can do in terms of opening up society”.
The “idea that we can open up everything and keep the virus under control” is wrong, he said, but it is clear that “schools are an absolute priority” for society.
However, the plan to pause shielding for the people most vulnerable to the effects of the virus will go ahead as planned from Saturday, according to the prime minister.
That means some 2.2 million people who have been self-isolating in England during the pandemic can return to work, if they cannot work from home, as long as their workplace is Covid-secure.
Guidance for employers will also change as planned from the start of August, giving employers “more discretion over how employees can work safely, whether by continuing to work from home, or attending a Covid-secure workplace”, Mr Johnson said.
According to the ONS, there is “now evidence to suggest a slight increase in the number of people in England testing positive on a nose and throat swab in recent weeks”.
A sample of households in England, excluding care homes and hospitals, were swabbed to test for current infection.
The ONS said daily cases had risen from an estimated 2,800 to 4,200 since last week.
However there is not enough data to suggest a higher proportion of positive tests in any particular region.
The latest announcement comes within hours of new lockdown rules in parts of England, banning separate households from meeting each other inside their homes and private gardens.
The rules, which came into force at midnight, impact people in Greater Manchester, east Lancashire, parts of West Yorkshire, and in Leicester.
They also ban members of two different households from mixing in pubs and restaurants, although individual households will still be able to visit such hospitality venues.
Health Secretary Matt Hancock told BBC Breakfast that the increase in transmission in the affected regions was due to people visiting friends and relatives, citing fresh data from contact tracing.
The changes come as Muslim communities prepare to celebrate Eid this weekend, and nearly four weeks after restrictions were eased across England – allowing people to meet indoors for the first time since late March.
Ministers have said police forces and councils will be given powers to enforce the new rules.
Areas included in announcement
Cases per 100,000 people
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