However, the move is "contingent on progress in the fight against coronavirus", and retailers will have to adhere to new guidelines to protect shoppers and workers, the PM added.

Outdoor markets and car showrooms will be able to reopen from 1 June.

It comes as the number of coronavirus deaths in the UK rose by 121 to 36,914.

Mr Johnson said new guidance had been published for the retail sector "detailing the measures they should take to meet the necessary social distancing and hygiene standards".

"Shops now have the time to implement this guidance before they reopen," he said.

"This will ensure there can be no doubt about what steps they should take."

'Much-needed clarity'

He added: "I want people to be confident that they can shop safely, provided they follow the social distancing rules for all premises."

Commenting on the development, Business Secretary Alok Sharma said: "Enabling these businesses to open will be a critical step on the road to rebuilding our economy, and will support millions of jobs across the UK."

The British Retail Consortium said it welcomed the announcement, adding it provided "much-needed clarity on the route ahead".

A spokesman for the Confederation of British Industry added that the new guidance would help retailers to open "safely and securely".

However, not all businesses are pleased with the announcement.

The British Association of Independent Retailers said many small shops had been preparing to open from next week, adding: "It is therefore a little disappointing for the smaller retailers not to be able to open until June 15, especially as they can make it safe to do so."

And analyst Catherine Shuttleworth, from the Savvy retail marketing agency, told the Today programme: "It is fine saying the stores can open, but are we going to have the appetite to go back?

"Shopping is a social, fun experience a lot of the time and social distancing takes that away. It's going to be a very different way of shopping from what we're used to."

'Extremely welcome news'

This is extremely welcome news for a sector that was struggling even before the pandemic.

The problem of falling footfall on the High Street looked like a walk in the park compared to months of shuttered windows.

When 15 June comes around, shops will look rather different to what we've been used to, with limits to the number of people allowed in, and restrictions on how people move around shops.

There might also be screens in place, and hygiene products on arrival.

However, some of these measures will be harder to implement than others - such as encouraging customers to avoid handling products while browsing.

The announcement at the daily Downing Street coronavirus briefing came after a lengthy press conference involving the PM's chief adviser, Dominic Cummings.

Mr Cummings has been facing calls to resign after it emerged he had driven his child and ill wife 260 miles from London to County Durham during lockdown.

But at the press conference, the former Vote Leave chief said he did not regret his actions and believed he had acted "reasonably" within the law.

On the subject of why he then drove his family to the town of Barnard Castle - 15 days after he had displayed symptoms - he said he was testing his eyesight to see if he could make the trip back down to London.

Asked about the matter at the daily briefing, Mr Johnson said: "Do I regret what has happened? Yes, of course I do regret the confusion and the anger and the pain that people feel."