A planned easing of England’s lockdown has been postponed a day before it was due to come into effect, as the Prime Minister warned the country “cannot be complacent” amid a rise in the prevalence of coronavirus in the community.

Measures due to be lifted on Saturday, including allowing small wedding receptions, reopening bowling alleys and casinos and pilots of larger gatherings in sports venues, have been delayed for at least two weeks.

And in a strengthening of precautions, Boris Johnson announced that face coverings will become mandatory in indoor settings such as museums, galleries, cinemas and places of worship from August 8.

In a Downing Street press conference on Friday, the Prime Minister revealed what he described as a “pretty punchy” new slogan – “Hands, face, space” – for people to be mindful of in their efforts to control the spread of Covid-19.

Standing alongside Mr Johnson, England’s chief medical officer, Professor Chris Whitty, warned that it might not be possible to ease lockdown further, saying the UK has “probably reached near the limit or the limits” of what can be done to reopen society.

Friday’s news came after local lockdown measures were announced in parts of the North West of England and areas of West Yorkshire, banning people from different households meeting indoors or in gardens following a spike in virus cases.

Mr Johnson told the briefing: “As we see these rises around the world, we can’t fool ourselves that we are exempt. We must be willing to react to the first signs of trouble.”

He added: “We cannot be complacent and I won’t stand by and allow this virus to threaten to cause more pain and more heartache in our country.

He said that, with numbers rising, “our assessment is that we should squeeze that brake pedal in order to keep the virus under control”.

Meanwhile on Friday:

– The ONS reported an increase in the number of people testing positive for coronavirus in England, with Mr Johnson saying the prevalence of the virus in the community is likely to be rising for the first time since May.

– Data released on Friday showed the R value for the UK is between 0.8 to 0.9, a slight rise from 0.7 to 0.9.

– It was confirmed sports events such as the snooker World Championships in Sheffield and the horseracing at Glorious Goodwood in West Sussex this weekend will now go ahead without fans.

– The decision to postpone plans to allow indoor performances was described as a “bitter blow for the music industry”.

– Scotland’s First Minister Nicola Sturgeon advised people not to travel across the border to those parts of northern England affected by a spike in coronavirus cases, while she said those returning should minimise contact with people from outside their household for 14 days.

– Muslim leaders criticised the Government for the “shockingly short notice” of the new restrictions in parts of northern England, announced the night before the Islamic festival of Eid.

On Thursday evening it was announced that people from different households in Greater Manchester, parts of east Lancashire and West Yorkshire would no longer be allowed to meet each other inside their homes or in gardens.

The new rules, which came into effect from midnight, also ban members of two different households from mixing in pubs, restaurants and other hospitality venues, but these businesses will remain open for those visiting individually or from the same household.

Prof Whitty told the briefing: “If we wish to do more things in the future, we may have to do less of some other things.

“And these will be difficult trade-offs, some of which will be decisions for Government and some of which are for all of us as citizens to do.

“But we have to be realistic about this. The idea that we can open up everything and keep the virus under control is clearly wrong.”

Other things which will not go ahead as planned across England on Saturday include indoor performances, reopening conference centres, and close-contact services such as facials and make-up application.

Despite the delay to the Government’s road map on reopening, Mr Johnson said he encouraged people “still to think of wonderful staycations here in the UK”.

Mr Johnson said that, while most people are following the rules, there will be a “greater police presence” to ensure the public is adhering to requirements around face coverings and stressed that local authorities can close down premises and cancel events which are not following the guidance.

Shielding advice will still be paused as planned on Saturday and the move to allow more discretion for employers with regard to staff returning to work will also go ahead, the Prime Minister said.

PA news agency understands that the pausing of shielding advice includes areas in the north west of England and Yorkshire where new restrictions were imposed on Thursday evening.

The Government will write to clinically vulnerable people living in areas where additional public health measures require them to continue shielding.

Accepting that Friday’s announcement would be a “real blow” to people who had wedding plans or those who can no longer celebrate Eid as they had hoped, Mr Johnson said “we simply cannot take the risk” but vowed to open up more fully “as soon as we possibly can”.