The wearing of face coverings will become mandatory in cinemas, museums, and places of worship from next weekend, Boris Johnson has announced.
In a press conference on Friday afternoon the prime minister said regulations would be extended to cover the new areas from Saturday 8 August.
Announcing the change alongside a slowing of planning lockdown lifting, Mr Johnson said: "We will also extend the requirement to wear a face covering to other indoor settings where you are likely to come into contact with people you do not normally meet, such as museums, galleries, cinemas and places of worship.
"We now recommend face coverings are worn in these settings, and this will become enforceable in law from August 8.
"At this stage, we are not changing the rules on social contact nationally. I don't want to tell people to spend less time with their friends. But unless people follow the rules and behave safely, we may need to go further."
He added: "Two weeks ago, I said we would hope for the best but plan for the worst. And of course we continue to hope for the best. The way to get there and to achieve that optimum outcome is if we all follow the rules, wash our hands, cover our faces, keep our distance - and get a test if we have symptoms, so that NHS Test and Trace can keep the virus under control.
"This is how we will avoid a return to full national lockdown. We've made huge progress together. I know we are going succeed and I know we are going to beat this - if each and every one of us plays our part."
Since 24 July the government has mandated the wearing of face masks inside shops, supermarkets and takeaway restaurants. They have been required on public transport for longer.
Chief medical officer Chris Whitty said on Friday that the UK had likely reached the limit of which parts of society it could open up without causing the virus to return – and that there would be trade-offs in future.
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